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What really separated AMPS from older systems is the "back end" call setup functionality. In AMPS, the cell centers could flexibly assign channels to handsets based on signal strength, allowing the same frequency to be re-used, without interference, if locations were separated enough. The channels were grouped so a specific set was different of the one used on the cell nearby. This allowed a larger number of phones to be supported over a geographical area. AMPS pioneers coined the term "cellular" because of its use of small hexagonal "cells" within a system.
AMPS suffered from many weaknesses compared to today's digital technologies. As an analog standard, it was susceptible to static and noise, and there was no protection from 'eavesdropping' using a scanner or an older TV set that could tune into channels 70–83.
Cloning.
In the 1990s, an epidemic of "cloning" cost the cellular carriers millions of dollars. An eavesdropper with specialized equipment could intercept a handset's ESN (Electronic Serial Number) and MDN or CTN (Mobile Directory Number or Cellular Telephone Number). The Electronic Serial Number, a 12-digit number sent by the handset to the cellular system for billing purposes, uniquely identified that phone on the network. The system then allowed or disallowed calls and/or features based on its customer file. A person intercepting an ESN/MDN pair could clone the combination onto a different phone and use it in other areas for making calls without paying.
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Cellular phone cloning became possible with off-the-shelf technology in the 1990s. Would-be cloners required three key items :
The radio, when tuned to the proper frequency, would receive the signal transmitted by the cell phone to be cloned, containing the phone's ESN/MDN pair. This signal would feed into the sound-card audio-input of the PC, and Banpaia would decode the ESN/MDN pair from this signal and display it on the screen. The hacker could then copy that data into the Oki 900 phone and reboot it, after which the phone network could not distinguish the Oki from the original phone whose signal had been received. This gave the cloner, through the Oki phone, the ability to use the mobile-phone service of the legitimate subscriber whose phone was cloned – just as if that phone had been physically stolen, except that the subscriber retained his or her phone, unaware that the phone had been cloned—at least until that subscriber received his or her next bill.
The problem became so large that some carriers required the use of a PIN before making calls. Eventually, the cellular companies initiated a system called RF Fingerprinting, whereby it could determine subtle differences in the signal of one phone from another and shut down some cloned phones. Some legitimate customers had problems with this though if they made certain changes to their own phone, such as replacing the battery and/or antenna.
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The Oki 900 could listen in to AMPS phone-calls right out-of-the-box with no hardware modifications.
Standards.
AMPS was originally standardized by American National Standards Institute (ANSI) as EIA/TIA/IS-3. EIA/TIA/IS-3 was superseded by EIA/TIA-553 and TIA interim standard with digital technologies, the cost of wireless service is so low that the problem of cloning has virtually disappeared.
Frequency bands.
AMPS cellular service operated in the 850 MHz Cellular band. For each market area, the United States Federal Communications Commission (FCC) allowed two licensees (networks) known as "A" and "B" carriers. Each carrier within a market used a specified "block" of frequencies consisting of 21 control channels and 395 voice channels. Originally, the B (wireline) side license was usually owned by the local phone company, and the A (non-wireline) license was given to wireless telephone providers.
At the inception of cellular in 1983, the FCC had granted each carrier within a market 333 channel pairs (666 channels total). By the late 1980s, the cellular industry's subscriber base had grown into the millions across America and it became necessary to add channels for additional capacity. In 1989, the FCC granted carriers an expansion from the previous 666 channels to the final 832 (416 pairs per carrier). The additional frequencies were from the band held in reserve for future (inevitable) expansion. These frequencies were immediately adjacent to the existing cellular band. These bands had previously been allocated to UHF TV channels 70–83.
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Each duplex channel was composed of 2 frequencies. 416 of these were in the 824–849 MHz range for transmissions from mobile stations to the base stations, paired with 416 frequencies in the 869–894 MHz range for transmissions from base stations to the mobile stations. Each cell site used a different subset of these channels than its neighbors to avoid interference. This significantly reduced the number of channels available at each site in real-world systems. Each AMPS channel had a one way bandwidth of 30 kHz, for a total of 60 kHz for each duplex channel.
Laws were passed in the US which prohibited the FCC type acceptance and sale of any receiver which could tune the frequency ranges occupied by analog AMPS cellular services. Though the service is no longer offered, these laws remain in force (although they may no longer be enforced).
Narrowband AMPS.
In 1991, Motorola proposed an AMPS enhancement known as narrowband AMPS (NAMPS or N-AMPS).
Digital AMPS.
Later, many AMPS networks were partially converted to D-AMPS, often referred to as TDMA (though TDMA is a generic term that applies to many 2G cellular systems). D-AMPS, commercially deployed since 1993, was a digital, 2G standard used mainly by AT&T Mobility and U.S. Cellular in the United States, Rogers Wireless in Canada, Telcel in Mexico, Telecom Italia Mobile (TIM) in Brazil, VimpelCom in Russia, Movilnet in Venezuela, and Cellcom in Israel. In most areas, D-AMPS is no longer offered and has been replaced by more advanced digital wireless networks.
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Successor technologies.
AMPS and D-AMPS have now been phased out in favor of either CDMA2000 or GSM, which allow for higher capacity data transfers for services such as WAP, Multimedia Messaging System (MMS), and wireless Internet access. There are some phones capable of supporting AMPS, D-AMPS and GSM all in one phone (using the GAIT standard).
Analog AMPS being replaced by digital.
In 2002, the FCC decided to no longer require A and B carriers to support AMPS service as of February 18, 2008. All AMPS carriers have converted to a digital standard such as CDMA2000 or GSM. Digital technologies such as GSM and CDMA2000 support multiple voice calls on the same channel and offer enhanced features such as two-way text messaging and data services.
Unlike in the United States, the Canadian Radio-television and Telecommunications Commission (CRTC) and Industry Canada have not set any requirement for maintaining AMPS service in Canada. Rogers Wireless has dismantled their AMPS (along with IS-136) network; the networks were shut down May 31, 2007. Bell Mobility and Telus Mobility, who operated AMPS networks in Canada, announced that they would observe the same timetable as outlined by the FCC in the United States, and as a result would not begin to dismantle their AMPS networks until after February 2008.
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OnStar relied heavily on North American AMPS service for its subscribers because, when the system was developed, AMPS offered the most comprehensive wireless coverage in the US. In 2006, ADT asked the FCC to extend the AMPS deadline due to many of their alarm systems still using analog technology to communicate with the control centers. Cellular companies who own an A or B license (such as Verizon and Alltel) were required to provide analog service until February 18, 2008. After that point, however, most cellular companies were eager to shut down AMPS and use the remaining channels for digital services. OnStar transitioned to digital service with the help of data transport technology developed by Airbiquity, but warned customers who could not be upgraded to digital service that their service would permanently expire on January 1, 2008.
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Aerodynamics
Aerodynamics ( "aero" (air) + (dynamics)) is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics, and is an important domain of study in aeronautics. The term "aerodynamics" is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer simulations has formed a rational basis for the development of heavier-than-air flight and a number of other technologies. Recent work in aerodynamics has focused on issues related to compressible flow, turbulence, and boundary layers and has become increasingly computational in nature.
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History.
Modern aerodynamics only dates back to the seventeenth century, but aerodynamic forces have been harnessed by humans for thousands of years in sailboats and windmills, and images and stories of flight appear throughout recorded history, such as the Ancient Greek legend of Icarus and Daedalus. Fundamental concepts of continuum, drag, and pressure gradients appear in the work of Aristotle and Archimedes.
In 1726, Sir Isaac Newton became the first person to develop a theory of air resistance, making him one of the first aerodynamicists. Dutch-Swiss mathematician Daniel Bernoulli followed in 1738 with "Hydrodynamica" in which he described a fundamental relationship between pressure, density, and flow velocity for incompressible flow known today as Bernoulli's principle, which provides one method for calculating aerodynamic lift. In 1757, Leonhard Euler published the more general Euler equations which could be applied to both compressible and incompressible flows. The Euler equations were extended to incorporate the effects of viscosity in the first half of the 1800s, resulting in the Navier–Stokes equations. The Navier–Stokes equations are the most general governing equations of fluid flow but are difficult to solve for the flow around all but the simplest of shapes.
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In 1799, Sir George Cayley became the first person to identify the four aerodynamic forces of flight (weight, lift, drag, and thrust), as well as the relationships between them, and in doing so outlined the path toward achieving heavier-than-air flight for the next century. In 1871, Francis Herbert Wenham constructed the first wind tunnel, allowing precise measurements of aerodynamic forces. Drag theories were developed by Jean le Rond d'Alembert, Gustav Kirchhoff, and Lord Rayleigh. In 1889, Charles Renard, a French aeronautical engineer, became the first person to reasonably predict the power needed for sustained flight. Otto Lilienthal, the first person to become highly successful with glider flights, was also the first to propose thin, curved airfoils that would produce high lift and low drag. Building on these developments as well as research carried out in their own wind tunnel, the Wright brothers flew the first powered airplane on December 17, 1903.
During the time of the first flights, Frederick W. Lanchester, Martin Kutta, and Nikolai Zhukovsky independently created theories that connected circulation of a fluid flow to lift. Kutta and Zhukovsky went on to develop a two-dimensional wing theory. Expanding upon the work of Lanchester, Ludwig Prandtl is credited with developing the mathematics behind thin-airfoil and lifting-line theories as well as work with boundary layers.
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As aircraft speed increased designers began to encounter challenges associated with air compressibility at speeds near the speed of sound. The differences in airflow under such conditions lead to problems in aircraft control, increased drag due to shock waves, and the threat of structural failure due to aeroelastic flutter. The ratio of the flow speed to the speed of sound was named the Mach number after Ernst Mach who was one of the first to investigate the properties of the supersonic flow. Macquorn Rankine and Pierre Henri Hugoniot independently developed the theory for flow properties before and after a shock wave, while Jakob Ackeret led the initial work of calculating the lift and drag of supersonic airfoils. Theodore von Kármán and Hugh Latimer Dryden introduced the term transonic to describe flow speeds between the critical Mach number and Mach 1 where drag increases rapidly. This rapid increase in drag led aerodynamicists and aviators to disagree on whether supersonic flight was achievable until the sound barrier was broken in 1947 using the Bell X-1 aircraft.
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By the time the sound barrier was broken, aerodynamicists' understanding of the subsonic and low supersonic flow had matured. The Cold War prompted the design of an ever-evolving line of high-performance aircraft. Computational fluid dynamics began as an effort to solve for flow properties around complex objects and has rapidly grown to the point where entire aircraft can be designed using computer software, with wind-tunnel tests followed by flight tests to confirm the computer predictions. Understanding of supersonic and hypersonic aerodynamics has matured since the 1960s, and the goals of aerodynamicists have shifted from the behaviour of fluid flow to the engineering of a vehicle such that it interacts predictably with the fluid flow. Designing aircraft for supersonic and hypersonic conditions, as well as the desire to improve the aerodynamic efficiency of current aircraft and propulsion systems, continues to motivate new research in aerodynamics, while work continues to be done on important problems in basic aerodynamic theory related to flow turbulence and the existence and uniqueness of analytical solutions to the Navier–Stokes equations.
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Fundamental concepts.
Understanding the motion of air around an object (often called a flow field) enables the calculation of forces and moments acting on the object. In many aerodynamics problems, the forces of interest are the fundamental forces of flight: lift, drag, thrust, and weight. Of these, lift and drag are aerodynamic forces, i.e. forces due to air flow over a solid body. Calculation of these quantities is often founded upon the assumption that the flow field behaves as a continuum. Continuum flow fields are characterized by properties such as flow velocity, pressure, density, and temperature, which may be functions of position and time. These properties may be directly or indirectly measured in aerodynamics experiments or calculated starting with the equations for conservation of mass, momentum, and energy in air flows. Density, flow velocity, and an additional property, viscosity, are used to classify flow fields.
Flow classification.
Flow velocity is used to classify flows according to speed regime. Subsonic flows are flow fields in which the air speed field is always below the local speed of sound. Transonic flows include both regions of subsonic flow and regions in which the local flow speed is greater than the local speed of sound. Supersonic flows are defined to be flows in which the flow speed is greater than the speed of sound everywhere. A fourth classification, hypersonic flow, refers to flows where the flow speed is much greater than the speed of sound. Aerodynamicists disagree on the precise definition of hypersonic flow.
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Compressible flow accounts for varying density within the flow. Subsonic flows are often idealized as incompressible, i.e. the density is assumed to be constant. Transonic and supersonic flows are compressible, and calculations that neglect the changes of density in these flow fields will yield inaccurate results.
Viscosity is associated with the frictional forces in a flow. In some flow fields, viscous effects are very small, and approximate solutions may safely neglect viscous effects. These approximations are called inviscid flows. Flows for which viscosity is not neglected are called viscous flows. Finally, aerodynamic problems may also be classified by the flow environment. External aerodynamics is the study of flow around solid objects of various shapes (e.g. around an airplane wing), while internal aerodynamics is the study of flow through passages inside solid objects (e.g. through a jet engine).
Continuum assumption.
Unlike liquids and solids, gases are composed of discrete molecules which occupy only a small fraction of the volume filled by the gas. On a molecular level, flow fields are made up of the collisions of many individual of gas molecules between themselves and with solid surfaces. However, in most aerodynamics applications, the discrete molecular nature of gases is ignored, and the flow field is assumed to behave as a continuum. This assumption allows fluid properties such as density and flow velocity to be defined everywhere within the flow.
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The validity of the continuum assumption is dependent on the density of the gas and the application in question. For the continuum assumption to be valid, the mean free path length must be much smaller than the length scale of the application in question. For example, many aerodynamics applications deal with aircraft flying in atmospheric conditions, where the mean free path length is on the order of micrometers and where the body is orders of magnitude larger. In these cases, the length scale of the aircraft ranges from a few meters to a few tens of meters, which is much larger than the mean free path length. For such applications, the continuum assumption is reasonable. The continuum assumption is less valid for extremely low-density flows, such as those encountered by vehicles at very high altitudes (e.g. 300,000 ft/90 km) or satellites in Low Earth orbit. In those cases, statistical mechanics is a more accurate method of solving the problem than is continuum aerodynamics. The Knudsen number can be used to guide the choice between statistical mechanics and the continuous formulation of aerodynamics.
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Conservation laws.
The assumption of a fluid continuum allows problems in aerodynamics to be solved using fluid dynamics conservation laws. Three conservation principles are used:
Together, these equations are known as the Navier–Stokes equations, although some authors define the term to only include the momentum equation(s). The Navier–Stokes equations have no known analytical solution and are solved in modern aerodynamics using computational techniques. Because computational methods using high speed computers were not historically available and the high computational cost of solving these complex equations now that they are available, simplifications of the Navier–Stokes equations have been and continue to be employed. The Euler equations are a set of similar conservation equations which neglect viscosity and may be used in cases where the effect of viscosity is expected to be small. Further simplifications lead to Laplace's equation and potential flow theory. Additionally, Bernoulli's equation is a solution in one dimension to both the momentum and energy conservation equations.
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The ideal gas law or another such equation of state is often used in conjunction with these equations to form a determined system that allows the solution for the unknown variables.
Branches of aerodynamics.
Aerodynamic problems are classified by the flow environment or properties of the flow, including flow speed, compressibility, and viscosity. "External" aerodynamics is the study of flow around solid objects of various shapes. Evaluating the lift and drag on an airplane or the shock waves that form in front of the nose of a rocket are examples of external aerodynamics. "Internal" aerodynamics is the study of flow through passages in solid objects. For instance, internal aerodynamics encompasses the study of the airflow through a jet engine or through an air conditioning pipe.
Aerodynamic problems can also be classified according to whether the flow speed is below, near or above the speed of sound. A problem is called subsonic if all the speeds in the problem are less than the speed of sound, transonic if speeds both below and above the speed of sound are present (normally when the characteristic speed is approximately the speed of sound), supersonic when the characteristic flow speed is greater than the speed of sound, and hypersonic when the flow speed is much greater than the speed of sound. Aerodynamicists disagree over the precise definition of hypersonic flow; a rough definition considers flows with Mach numbers above 5 to be hypersonic.
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The influence of viscosity on the flow dictates a third classification. Some problems may encounter only very small viscous effects, in which case viscosity can be considered to be negligible. The approximations to these problems are called inviscid flows. Flows for which viscosity cannot be neglected are called viscous flows.
Incompressible aerodynamics.
An incompressible flow is a flow in which density is constant in both time and space. Although all real fluids are compressible, a flow is often approximated as incompressible if the effect of the density changes cause only small changes to the calculated results. This is more likely to be true when the flow speeds are significantly lower than the speed of sound. Effects of compressibility are more significant at speeds close to or above the speed of sound. The Mach number is used to evaluate whether the incompressibility can be assumed, otherwise the effects of compressibility must be included.
Subsonic flow.
Subsonic (or low-speed) aerodynamics describes fluid motion in flows which are much lower than the speed of sound everywhere in the flow. There are several branches of subsonic flow but one special case arises when the flow is inviscid, incompressible and irrotational. This case is called potential flow and allows the differential equations that describe the flow to be a simplified version of the equations of fluid dynamics, thus making available to the aerodynamicist a range of quick and easy solutions.
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In solving a subsonic problem, one decision to be made by the aerodynamicist is whether to incorporate the effects of compressibility. Compressibility is a description of the amount of change of density in the flow. When the effects of compressibility on the solution are small, the assumption that density is constant may be made. The problem is then an incompressible low-speed aerodynamics problem. When the density is allowed to vary, the flow is called compressible. In air, compressibility effects are usually ignored when the Mach number in the flow does not exceed 0.3 (about 335 feet (102 m) per second or 228 miles (366 km) per hour at 60 °F (16 °C)). Above Mach 0.3, the problem flow should be described using compressible aerodynamics.
Compressible aerodynamics.
According to the theory of aerodynamics, a flow is considered to be compressible if the density changes along a streamline. This means that – unlike incompressible flow – changes in density are considered. In general, this is the case where the Mach number in part or all of the flow exceeds 0.3. The Mach 0.3 value is rather arbitrary, but it is used because gas flows with a Mach number below that value demonstrate changes in density of less than 5%. Furthermore, that maximum 5% density change occurs at the stagnation point (the point on the object where flow speed is zero), while the density changes around the rest of the object will be significantly lower. Transonic, supersonic, and hypersonic flows are all compressible flows.
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Transonic flow.
The term Transonic refers to a range of flow velocities just below and above the local speed of sound (generally taken as Mach 0.8–1.2). It is defined as the range of speeds between the critical Mach number, when some parts of the airflow over an aircraft become supersonic, and a higher speed, typically near Mach 1.2, when all of the airflow is supersonic. Between these speeds, some of the airflow is supersonic, while some of the airflow is not supersonic.
Supersonic flow.
Supersonic aerodynamic problems are those involving flow speeds greater than the speed of sound. Calculating the lift on the Concorde during cruise can be an example of a supersonic aerodynamic problem.
Supersonic flow behaves very differently from subsonic flow. Fluids react to differences in pressure; pressure changes are how a fluid is "told" to respond to its environment. Therefore, since sound is, in fact, an infinitesimal pressure difference propagating through a fluid, the speed of sound in that fluid can be considered the fastest speed that "information" can travel in the flow.
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Therefore, since sound is, in fact, an infinitesimal pressure difference propagating through a fluid, the speed of sound in that fluid can be considered the fastest speed that "information" can travel in the flow. This difference most obviously manifests itself in the case of a fluid striking an object. In front of that object, the fluid builds up a stagnation pressure as impact with the object brings the moving fluid to rest. In fluid traveling at subsonic speed, this pressure disturbance can propagate upstream, changing the flow pattern ahead of the object and giving the impression that the fluid "knows" the object is there by seemingly adjusting its movement and is flowing around it. In a supersonic flow, however, the pressure disturbance cannot propagate upstream. Thus, when the fluid finally reaches the object it strikes it and the fluid is forced to change its properties – temperature, density, pressure, and Mach number—in an extremely violent and irreversible fashion called a shock wave. The presence of shock waves, along with the compressibility effects of high-flow velocity (see Reynolds number) fluids, is the central difference between the supersonic and subsonic aerodynamics regimes.
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Hypersonic flow.
In aerodynamics, hypersonic speeds are speeds that are highly supersonic. In the 1970s, the term generally came to refer to speeds of Mach 5 (5 times the speed of sound) and above. The hypersonic regime is a subset of the supersonic regime. Hypersonic flow is characterized by high temperature flow behind a shock wave, viscous interaction, and chemical dissociation of gas.
Associated terminology.
The incompressible and compressible flow regimes produce many associated phenomena, such as boundary layers and turbulence.
Boundary layers.
The concept of a boundary layer is important in many problems in aerodynamics. The viscosity and fluid friction in the air is approximated as being significant only in this thin layer. This assumption makes the description of such aerodynamics much more tractable mathematically.
Turbulence.
In aerodynamics, turbulence is characterized by chaotic property changes in the flow. These include low momentum diffusion, high momentum convection, and rapid variation of pressure and flow velocity in space and time. Flow that is not turbulent is called laminar flow.
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Aerodynamics in other fields.
Engineering design.
Aerodynamics is a significant element of vehicle design, including road cars and trucks where the main goal is to reduce the vehicle drag coefficient, and racing cars, where in addition to reducing drag the goal is also to increase the overall level of downforce. Aerodynamics is also important in the prediction of forces and moments acting on sailing vessels. It is used in the design of mechanical components such as hard drive heads. Structural engineers resort to aerodynamics, and particularly aeroelasticity, when calculating wind loads in the design of large buildings, bridges, and wind turbines.
The aerodynamics of internal passages is important in heating/ventilation, gas piping, and in automotive engines where detailed flow patterns strongly affect the performance of the engine.
Environmental design.
Urban aerodynamics are studied by town planners and designers seeking to improve amenity in outdoor spaces, or in creating urban microclimates to reduce the effects of urban pollution. The field of environmental aerodynamics describes ways in which atmospheric circulation and flight mechanics affect ecosystems.
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Aerodynamic equations are used in numerical weather prediction.
Ball-control in sports.
Sports in which aerodynamics are of crucial importance include soccer, table tennis, cricket, baseball, and golf, in which most players can control the trajectory of the ball using the "Magnus effect".
Further reading.
General aerodynamics
Subsonic aerodynamics
Transonic aerodynamics
Supersonic aerodynamics
Hypersonic aerodynamics
History of aerodynamics
Aerodynamics related to engineering
"Ground vehicles"
"Fixed-wing aircraft"
"Helicopters"
"Missiles"
"Model aircraft"
Related branches of aerodynamics
"Aerothermodynamics"
"Aeroelasticity"
"Boundary layers"
"Turbulence"
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Andreas Schlüter
Andreas Schlüter (1659 – ) was a German baroque sculptor and architect, active in the Holy Roman Empire, the Polish–Lithuanian Commonwealth, and Russia.
Biography.
Andreas Schlüter was born probably in Hamburg. His early life is obscure as at least three different persons of that name are documented. The records of St. Michaelis Church, Hamburg show that an Andreas Schlüter, son of sculptor Gerhart Schlüter, had been baptized there on 22 May 1664. Documents from Gdańsk reported that an Andreas Schlüter "(senior)" had worked 1640–1652 in Gdańsk's Jopengasse lane (today's ulica Piwna). Possibly born in 1640, an "Andres Schliter" is recorded as apprentice on 9 May 1656 by the mason's guild. Other sources state 1659 as year of birth.
He probably did spend several years abroad as Journeyman. His first work, in 1675, may have been epitaphs of the Dukes Sambor and Mestwin in the dome of Pelplin monastery.
Schlüter's first known work was the decoration of the facade of the Gdańsk Royal Chapel, in 1681. He later created statues for King John III Sobieski's Wilanów Palace in Warsaw and sepulchral sculptures in Zhovkva. In 1689, he moved to Warsaw and made the pediment reliefs and sculptural work of Krasiński Palace.
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Schlüter was invited to Berlin in 1694 by Eberhard von Danckelmann to work as court sculptor at the armory ("Zeughaus") for Elector Frederick III. His sculpted decorations are a masterpiece of baroque expression and pathos. While the more visible reliefs on the outside had to praise fighting, the statues of dying warriors in the interior denounced war and gave an indication of his pacifist religious beliefs (he is said to have been a Mennonite). Travelling through Italy in 1696, he studied the work of masters like Michelangelo Buonarroti and Gian Lorenzo Bernini.
Schlüter also worked as an architect and built many state buildings in Berlin in his role as "Hofbaumeister" (Court Architect), which he lost when one tower showed signs of a weak fundament. He also served as director of the Prussian Academy of Arts from 1702 to 1704, after which he began concentrating on sculpting again, as "Hofbildhauer" (Court Sculptor). His most important equestrian sculpture is that of the "Great Elector", Frederick William of Brandenburg, cast in 1708 and placed at "Lange Brücke" near the Berlin City Palace, now situated in the honor court before Charlottenburg Palace.
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The Berlin City Palace, and many of his works, were partially destroyed by bombing in World War II and by the subsequent Communist regime. A similar fate probably befell the Amber Room, made between 1701 and 1709, Schlüter's most famous work of architecture.
The Berlin City Palace was reconstructed between 2013 and 2020.
In 1713, Schlüter's fame brought him to work for Tsar Peter I of Russia in Saint Petersburg, where he died of an illness after creating several designs. Together with Johann Friedrich Braunstein, he designed the Grand Palace and Monplaisir Palace in Peterhof Palace Complex. Also the city's oldest building, Kikin Hall, and the reliefs at the Summer Palace are attributed to him. This way he became an important figure of Petrine Baroque.
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Ash
Ash is the solid remnants of fires. Specifically, "ash" refers to all non-aqueous, non-gaseous residues that remain after something burns. In analytical chemistry, to analyse the mineral and metal content of chemical samples, ash is the non-gaseous, non-liquid residue after complete combustion.
Ashes as the end product of incomplete combustion are mostly mineral, but usually still contain an amount of combustible organic or other oxidizable residues. The best-known type of ash is wood ash, as a product of wood combustion in campfires, fireplaces, etc. The darker the wood ashes, the higher the content of remaining charcoal from incomplete combustion. The ashes are of different types. Some ashes contain natural compounds that make soil fertile. Others have chemical compounds that can be toxic but may break up in soil from chemical changes and microorganism activity.
Like soap, ash is also a disinfecting agent (alkaline). The World Health Organization recommends ash or sand as alternative for handwashing when soap is not available. Before industrialization, ash soaked in water was the primary means of obtaining potash.
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Natural occurrence.
Ash occurs naturally from any fire that burns vegetation, and may disperse in the soil to fertilise it, or clump under it for long enough to carbonise into coal.
Composition.
The composition of the ash varies depending on the product burned and its origin. The "ash content" or "mineral content" of a product is derived its incineration under temperatures ranging from to .
Wood and plant matter.
The composition of ash derived from wood and other plant matter varies based on plant species, parts of the plants (such as bark, trunk, or young branches with foliage), type of soil, and time of year. The composition of these ashes also differ greatly depending on mode of combustion.
Wood ashes, in addition to residual carbonaceous materials (unconsumed embers, activated carbons impregnated with carbonaceous particles, tars, various gases, etc.), contain a between 20% and 50% calcium in the form of calcium oxide and are generally rich in potassium carbonate. Ashes derived from grasses, and the Gramineae family in particular, are rich in silica. The color of the ash comes from small proportions of inorganic minerals such as iron oxides and manganese. The oxidized metal elements that constitute wood ash are mostly considered alkaline.
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For example, ash collected from wood boilers is composed of
The pH of the ash is between 10 and 13, mostly due to the fact that the oxides of calcium, potassium, and sodium are strong bases. Acidic components such as carbon dioxide, phosphoric acid, silicic acid, and sulfuric acid are rarely present and, in the presence of the previously mentioned bases, are generally found in the form of salts, respectively carbonates, phosphates, silicates and sulphates.
Strictly speaking, calcium and potassium salts produce the aforementioned calcium oxide (also known as quicklime) and potassium during the combustion of organic matter. But, in practice, quicklime is only obtained via lime-kiln, and potash (from potassium carbonate) or baking soda (from sodium carbonate) is extracted from the ashes.
Other substances such as sulfur, chlorine, iron or sodium only appear in small quantities. Still others are rarely found in wood, such as aluminum, zinc, and boron. (depending on the trace elements drawn from the soil by the incinerated plants).
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Mineral content in ash depends on the species of tree burned, even in the same soil conditions. More chloride is found in conifer trees than broadleaf trees, with seven times as much found in spruces than in oak trees. There is twice as much phosphoric acid in the European aspen than in oaks and twice as much magnesium in elm trees than in the Scotch pine.
Ash composition also varies by which part of the tree was burnt. Silicon and calcium salts are more abundant in bark than in wood, while potassium salts are primarily found in wood. Compositional variation also occurred based on the season in which the tree died.
Specific types.
Cremation ashes.
Cremation ashes, also called cremated remains or "cremains," are the bodily remains left from cremation. They often take the form of a grey powder resembling coarse sand. While often referred to as "ashes", the remains primarily consist of powdered bone fragments due to the cremation process, which eliminates the body's organic materials. People often store these ashes in containers like urns, although they are also sometimes buried or scattered in specific locations.
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Food ashes.
In food processing, mineral and ash content is used to characterize the presence of organic and inorganic components in food for monitoring quality, nutritional quantification and labeling, analyzing microbiological stability, and more. This process can be used to measure minerals like calcium, sodium, potassium, and phosphorus as well as metal content such as lead, mercury, cadmium, and aluminum.
Joss paper ash.
Analysis of the contents of ash samples from Vietnam and Singapore shows that joss paper burning can emit many pollutants detrimental to air quality. There is a significant amount of heavy metals in the dust fume and bottom ash, e.g., aluminium, iron, manganese, copper, lead, zinc and cadmium.
"Burning of joss paper accounted for up to 42% of the atmospheric rBC [refractory black carbon] mass, higher than traffic (14-17%), crop residue (10-17%), coal (18-20%) during the Hanyi festival in northwest China", according to a 2022 study, "the overall air quality can be worsened due to the practice of uncontrolled burning of joss paper during the festival, which is not just confined to the people who do the burning," and "burning joss paper during worship activities is common in China and most Asian countries with similar traditions."
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The composition of joss paper ash largely depends on the types / composition of the joss paper goods being burnt, and there are many of them.
Wildfire ash.
High levels of heavy metals, including lead, arsenic, cadmium, and copper were found in the ash debris following the 2007 Californian wildfires. A national clean-up campaign was organised ... In the devastating California Camp Fire (2018) that killed 85 people, lead levels increased by around 50 times in the hours following the fire at a site nearby (Chico). Zinc concentration also increased significantly in Modesto, 150 miles away. Heavy metals such as manganese and calcium were found in numerous California fires as well.
Uses.
Fertilizer.
Ashes have been used since the Neolithic period as fertilizer because they are rich in minerals, especially potash and essential nutrients. They are the main fertilizer in slash-and-burn agriculture, which eventually evolved into controlled burn and forest clearing practices. People in ancient history already possessed extensive knowledge of the nutrients produced by (from social 10th textbook)(manufacturing industries) different ashes. For clay soil in particular, using ash without modification or using , ash whose minerals have been washed with water, was necessary.
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Laundry.
Because ashes contain potash, they can be used to make biodegradable laundry detergent. The demand for organic products has led to renewed interest for laundry using ash derived from wood. The French word for laundry is from the Latin word , which means a substance made from ash and used to wash laundry. This usage also developed into a small, traditional architectural structure to the west of Rhône mainstem: the , a masonry structure built with stone or cob, that looks like a cabinet and that carries dirty laundry and fireplace ash; when the is full, the laundry and ash are moved to a laundry container and boiled in water.
Laundry using ash derived from wood has the benefit of being free, easy to produce, sustainable, and as efficient as standard laundry washing methods.
Effect on precipitation.
"Particles of dust or smoke in the atmosphere are essential for precipitation. These particles, called 'condensation nuclei,' provide a surface for water vapor to condense upon. This helps water droplets gather together and become large enough to fall to the earth."
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Antiderivative
In calculus, an antiderivative, inverse derivative, primitive function, primitive integral or indefinite integral of a continuous function is a differentiable function whose derivative is equal to the original function . This can be stated symbolically as . The process of solving for antiderivatives is called antidifferentiation (or indefinite integration), and its opposite operation is called "differentiation", which is the process of finding a derivative. Antiderivatives are often denoted by capital Roman letters such as and .
Antiderivatives are related to definite integrals through the second fundamental theorem of calculus: the definite integral of a function over a closed interval where the function is Riemann integrable is equal to the difference between the values of an antiderivative evaluated at the endpoints of the interval.
In physics, antiderivatives arise in the context of rectilinear motion (e.g., in explaining the relationship between position, velocity and acceleration). The discrete equivalent of the notion of antiderivative is antidifference.
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Examples.
The function formula_1 is an antiderivative of formula_2, since the derivative of formula_3 is formula_4. Since the derivative of a constant is zero, formula_4 will have an infinite number of antiderivatives, such as formula_6, etc. Thus, all the antiderivatives of formula_4 can be obtained by changing the value of in formula_8, where is an arbitrary constant known as the constant of integration. The graphs of antiderivatives of a given function are vertical translations of each other, with each graph's vertical location depending upon the value .
More generally, the power function formula_9 has antiderivative formula_10 if , and formula_11 if .
In physics, the integration of acceleration yields velocity plus a constant. The constant is the initial velocity term that would be lost upon taking the derivative of velocity, because the derivative of a constant term is zero. This same pattern applies to further integrations and derivatives of motion (position, velocity, acceleration, and so on). Thus, integration produces the relations of acceleration, velocity and displacement:
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formula_12
Uses and properties.
Antiderivatives can be used to compute definite integrals, using the fundamental theorem of calculus: if is an antiderivative of the continuous function over the interval formula_13, then:
formula_14
Because of this, each of the infinitely many antiderivatives of a given function may be called the "indefinite integral" of "f" and written using the integral symbol with no bounds:
formula_15
If is an antiderivative of , and the function is defined on some interval, then every other antiderivative of differs from by a constant: there exists a number such that formula_16 for all . is called the constant of integration. If the domain of is a disjoint union of two or more (open) intervals, then a different constant of integration may be chosen for each of the intervals. For instance
formula_17
is the most general antiderivative of formula_18 on its natural domain formula_19
Every continuous function has an antiderivative, and one antiderivative is given by the definite integral of with variable upper boundary:
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formula_20
for any in the domain of . Varying the lower boundary produces other antiderivatives, but not necessarily all possible antiderivatives. This is another formulation of the fundamental theorem of calculus.
There are many elementary functions whose antiderivatives, even though they exist, cannot be expressed in terms of elementary functions. Elementary functions are polynomials, exponential functions, logarithms, trigonometric functions, inverse trigonometric functions and their combinations under composition and linear combination. Examples of these nonelementary integrals are
For a more detailed discussion, see also Differential Galois theory.
Techniques of integration.
Finding antiderivatives of elementary functions is often considerably harder than finding their derivatives (indeed, there is no pre-defined method for computing indefinite integrals). For some elementary functions, it is impossible to find an antiderivative in terms of other elementary functions. To learn more, see elementary functions and nonelementary integral.
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There exist many properties and techniques for finding antiderivatives. These include, among others:
Computer algebra systems can be used to automate some or all of the work involved in the symbolic techniques above, which is particularly useful when the algebraic manipulations involved are very complex or lengthy. Integrals which have already been derived can be looked up in a table of integrals.
Of non-continuous functions.
Non-continuous functions can have antiderivatives. While there are still open questions in this area, it is known that:
Assuming that the domains of the functions are open intervals:
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The ABC Song
"The ABC Song" is the best-known song used to recite the English alphabet in alphabetical order. It is commonly used to teach the alphabet to children in English-speaking countries. "The ABC Song" was first copyrighted in 1835 by Boston music publisher Charles Bradlee. The melody is from a 1761 French music book and is also used in other nursery rhymes like "Twinkle, Twinkle, Little Star", while the author of the lyrics is unknown. Songs set to the same melody are also used to teach the alphabets of other languages.
History.
The melody of "The ABC Song" was first published in the French book of music "Les Amusements d'une Heure et Demy" ("") (1761) without lyrics. It was adapted in Mozart's Twelve Variations and used in many nursery rhymes around the world, including "Ah! vous dirai-je, maman", "Twinkle, Twinkle, Little Star" and later "Baa, Baa, Black Sheep", before being used in this song. The author of the lyrics is unknown.
"The ABC Song" was first copyrighted in 1835 by Boston music publisher Charles Bradlee under the title "The A.B.C., a German air with variations for the flute with an easy accompaniment for the piano forte." The melody was attributed to 18th-century composer Louis Le Maire.
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"The ABC Song" is commonly used in preschools across English-speaking countries. Due to the speed at which '"L, M, N, O, P"' is spoken, it is a common misconception among children still learning the alphabet to believe that it is in fact its own letter called "elemenopee". Some have proposed teaching slower versions of the song to avoid this issue, but attempts to do so have been criticized for lacking the end rhymes and the "'L, M, N, O, P"" part being an essential part of the song. The television series "Sesame Street" has covered the song many times, collaborating with popular artists such as Stevie Wonder, Katy Perry, Nina Simone and Usher.
Composition and variations.
Lyrics: "(each line represents two measures, or eight beats)"
<score lang="lilypond" sound="1">\relative c' {
\key c \major \time 4/4
c4 c4 g'4 g4 \bar "|" a4 a4 g2 \bar "|"
f4 f4 e4 e4 \bar "|" d8 d8 d8 d8 c2 \bar "|" \break
g'4 g4 f2 \bar "|" e4 e4 d2 \bar "|"
g8 g8 g4 f2 \bar "|" e4 e4 d2 \bar "|" \break
c4 c4 g'4 g4 \bar "|" a4 a4 g2 \bar "|"
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f4 f4 e4 e4 \bar "|" d4 d4 c2 \bar "|."
\addlyrics {
A B C D E F G,
H I J K L M N O P,
Q R S, T U V,
W X, Y and Z.
Now I know my A B Cs.
Next time, won't you sing with me?
}</score>
Lyrics for the alternate Zed version: "(each line represents two measures or eight beats)"
<score lang="lilypond" sound="1">
\relative c' {
\key c \major \time 4/4
c4 c4 g'4 g4 \bar "|" a4 a4 g2 \bar "|"
f4 f4 e4 e4 \bar "|" d4 d4 c2 \bar "|" \break
g'4 g4 f4 f4 \bar "|" e4 e4 d2 \bar "|"
g4 g8 g8 f4 f4 \bar "|" e4 e4 d2 \bar "|" \break
c4 c4 g'4 g4 \bar "|" a4 a4 g2 \bar "|"
f4 f4 e4 e4 \bar "|" d4 d4 c2 \bar "|."
\addlyrics {
A B C D E F G,
H I J K L M N,
O P Q R S T U,
V W X Y and Z.
Now I know my A B Cs.
Next time, won't you sing with me?
</score>
Pronunciation of "Z".
In American English, the dialect in mind by the composer, the letter name for Z is pronounced /ziː/ ("Zee"), but in most other anglophone countries, the letter name is pronounced /zɛd/ ("Zed"). In such dialects, the absent "Zee"-rhyme is generally not missed, although while singing the song, some children may accommodate for "Zee" which they would otherwise not use on a regular basis. Variants of the song exist to accommodate "Zed". One such variation is shown below:
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<score sound="1">{ \time 4/4 c'4 c' g' g' | a' a' g'2 | f'4 f' e' e' | d' d' c'2 | g'4 g' f' f' | e' e' d'2 | g'4 \times 2/3 { f'8 f' f' } e'4 d' | c' r r2 | \bar "|." } \addlyrics { A B C D E F G H I J K L M N O P Q R S T U V dub- a- U X Y "Z(ed)" }</score>
This version does not have a closing line, and the tune is modified accordingly. The W is not lengthened in this version.
Backwards alphabet.
Several versions exist covering the alphabet backward, i.e., Z to A. One version is shown below.
The e-d-c-b part is as fast as the l-m-n-o part in the normal alphabet song.
Versions for other languages.
The same melody used for "The ABC Song" has also been used for the Spanish, German, French, and Arabic alphabets. A French-language version of the song is also taught in Canada, with generally no alterations to the melody except in the final line that requires adjustment to accommodate the two-syllable pronunciation of the French "y".
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Antigonid dynasty
The Antigonid dynasty (; ) was a Macedonian Greek royal house which ruled the kingdom of Macedon during the Hellenistic period. Founded by Antigonus I Monophthalmus, a general and successor of Alexander the Great, the dynasty first came to power after the Battle of Salamis in 306 BC and ruled much of Hellenistic Greece from 294 until their defeat at the Battle of Pydna in 168 BC (Third Macedonian War), after which Macedon came under the control of the Roman Republic.
The wars of the Diadochi witnessed the fall of the Argead dynasty in Macedon resulting in a power vacuum, which the Antigonid and Antipatrid dynasties sought to occupy. The Antigonid family first rose to power when Demetrius I Poliorcetes, son of Antigonus I, ousted Cassander's governor of Athens in 306 BC giving his father control over a land spanning from the Aegean Sea to the Middle East. Despite the subsequent instability and loss of the Asian territory, the family managed to maintain its power in mainland Greece and the islands, with Antigonus II Gonatas ultimately solidifying Antigonid rule over Hellenistic Macedon –a territory also known as the Antigonid Empire. Antigonus III Doson further expanded Macedonian influence in southern Greece reestablishing the Hellenic Alliance with himself as the president. Under Philip V, Antigonid Macedon first came into conflict with Rome, which had become a decisive power in the eastern Mediterranean. In the second century BC, the last Antigonid king, Perseus, became known as the champion of Greek resistance against Rome, albeit Rome's control over Antigonid Greece began to steadily expand, culminating in the fall of the dynasty in 168.
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History.
The beginning of Hellenistic Greece was defined by the struggle between the Antipatrid dynasty, led first by Cassander (r. 305 – 297 BC), son of Antipater, and the Antigonid dynasty, led by Antigonus I Monophthalmus (r. 306 – 301 BC) and his son, the future king Demetrius I Poliorcetes (r. 294 – 288 BC). After the power crisis in Macedon, which culminated in Philip III's and Euridice's death, Cassander managed to seize control from Olympias and began to establish his authority in the kingdom; in 316 BC he buried Philip III and Euridice at Aegae and married Philip II's daughter, Thessalonica, thus becoming a member of the Argead dynasty. In 310/309 BC, Cassander commanded Glaucias to secretly assassinate the 14-year-old Alexander IV, son of Alexander the Great, and his mother Roxane and the Macedonian Argead dynasty became extinct.
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Legacy.
The Antigonid was one of four dynasties established by Alexander's successors, the others being the Seleucid dynasty, Ptolemaic dynasty and Antipatrid dynasty. The last scion of the dynasty, Perseus of Macedon, who reigned between 179 and 168 BC, proved unable to stop the advancing Roman legions and Macedon's defeat at the Battle of Pydna signaled the end of the dynasty.
Dynasty.
The ruling members of the Antigonid dynasty were:
The Greek rebel against Rome and last King of Macedonia, Andriscus, claimed to be the son of Perseus.
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Abingdon
Abingdon may refer to:
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Abjuration
Abjuration is the solemn repudiation, abandonment, or renunciation by or upon oath, often the renunciation of citizenship or some other right or privilege. The term comes from the Latin "abjurare", "to forswear".
Abjuration of the realm.
Abjuration of the realm was a type of abjuration in ancient English law. The person taking the oath swore to leave the country directly and promptly, never to return to the kingdom unless by permission of the sovereign. This was often taken by fugitives who had taken sanctuary:
English Commonwealth.
Near the start of the English Civil War, on 18 August 1643 Parliament passed "An Ordinance for Explanation of a former Ordinance for Sequestration of Delinquents Estates with some Enlargements." The enlargements included an oath which became known as the "Oath of Abjuration":
In 1656–7, it was reissued in what was for Catholics an even more objectionable form. Everyone was to be "adjudged a Papist" who refused this oath, and the consequent penalties began with the confiscation of two-thirds of the recusant's goods, and went on to deprive him of almost every civic right.
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The Catholic Encyclopaedia makes the point that the oath and the penalties were so severe that it stopped the efforts of the Gallicanizing party among the English Catholics, who had been ready to offer forms of submission similar to the old oath of Allegiance, which was condemned anew about this time by Pope Innocent X.
Scotland.
During The Killing Time of the 1680s an Abjuration Oath could be put to suspects where they were given the option to abjure or renounce their allegiances. The terms of the oath were deliberately designed to offend the consciences of the Presbyterian Covenanters. Those who would not swear "whether they have arms, or not" could be "immediately killed" by field trial "before two witnesses" on a charge of high treason. John Brown was included among those executed in this judicial process by John Graham (Bluidy Clavers) on 1 May 1685. The wives and children of such men could also be put out of their houses if they had spoken to the suspect or refused the oath themselves.
Great Britain and Ireland.
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In England (and after 1707 Great Britain) the Oath of Abjuration denied the royal title of James II's heirs (i.e. the direct Catholic descendant of the House of Stuart exiled after the Glorious Revolution in 1688). In England, an Oath of Abjuration was taken by Members of Parliament, clergy, and laymen, pledging to support the current British monarch and repudiated the right of the Stuarts and other claimants to the throne. This oath was imposed under William III, George I and George III. It was superseded by the oath of allegiance. In Ireland, the oath was imposed of state officeholders, teachers, lawyers, and on the clergy of the established church in from 1703, the following year it was on all Irish voters and from 1709 it could be demanded of any adult male by a magistrate.
Bilino Polje abjuration.
The Bilino Polje abjuration, also known as "Confessio Christianorum bosniensis", was an act of alleged heresy abjuration by clergy of the Bosnian Church in presence of the Bosnian ruler, Ban Kulin, and Giovanni da Casamari. It affirmed the primacy of the pope and related to errors of practice, stemming from ignorance, rather than heretical doctrines. It was signed by seven Bosnian priors, on 8 April 1203 at Bilino Polje field, near today town of Zenica, in Bosnia and Herzegovina. The same document was brought to Buda, in 30 April by Giovanni da Casamari, Ban Kulin and two abbots, where it was examined by Emeric, King of Hungary, and the high clergy.
The Netherlands.
Another famous abjuration was brought about by the Plakkaat van Verlatinghe of July 26, 1581, the formal Act of Abjuration or declaration of independence of the Low Countries from the Spanish king, Philip II. This oath was the climax of the Eighty Years' War (Dutch Revolt).
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Abitibi
Abitibi may refer to:
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A Vindication of the Rights of Woman
A Vindication of the Rights of Woman: with Strictures on Political and Moral Subjects , is a 1792 feminist essay written by British philosopher and women's rights advocate Mary Wollstonecraft (1759–1797), and is one of the earliest works of feminist philosophy. In it, Wollstonecraft responds to those educational and political theorists of the eighteenth century who did not believe women should receive a rational education. She argues that women ought to have an education commensurate with their position in society, claiming that women are essential to the nation because they educate its children and because they could be "companions" to their husbands, rather than mere wives. Instead of viewing women as ornaments to society or property to be traded in marriage, Wollstonecraft maintains that they are human beings deserving of the same fundamental rights as men.
Wollstonecraft was prompted to write the "Rights of Woman" after reading Charles Maurice de Talleyrand-Périgord's 1791 report to the French National Assembly, which stated that women should only receive domestic education. From her reaction to this specific event, she launched a broad attack against double standards, indicting men for encouraging women to indulge in excessive emotion. Wollstonecraft hurried to complete the work in direct response to ongoing events; she intended to write a more thoughtful second volume but died before completing it.
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While Wollstonecraft does call for equality between the sexes in particular areas of life, especially morality, she does not explicitly state that men and women are equal. Her ambiguous statements regarding the equality of the sexes have made it difficult to classify Wollstonecraft as a modern feminist; the word itself did not emerge until decades after her death.
Although it is commonly assumed that the "Rights of Woman" was unfavourably received, this is a modern misconception based on the belief that Wollstonecraft was as reviled during her lifetime as she became after the publication of William Godwin's "Memoirs of the Author of A Vindication of the Rights of Woman" (1798). The "Rights of Woman" was generally received well when it was first published in 1792. Biographer Emily W. Sunstein called it "perhaps the most original book of [Wollstonecraft's] century". Wollstonecraft's work had significant impact on advocates for women's rights in the nineteenth century, particularly the 1848 Seneca Falls Convention which produced the Declaration of Sentiments laying out the aims of the women's suffrage movement in the United States.
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Historical context.
"A Vindication of the Rights of Woman" was written against the tumultuous background of the French Revolution and the debates that it spawned in Britain. In a lively and sometimes vicious pamphlet war, now referred to as the Revolution controversy, British political commentators addressed topics ranging from representative government to human rights to the separation of church and state, many of these issues having been raised in France first. Wollstonecraft first entered this fray in 1790 with "A Vindication of the Rights of Men", a response to Edmund Burke's "Reflections on the Revolution in France" (1790). In his "Reflections", Burke criticized the view of many British thinkers and writers who had welcomed the early stages of the French revolution. While they saw the revolution as analogous to Britain's own Glorious Revolution in 1688, which had restricted the powers of the monarchy, Burke argued that the appropriate historical analogy was the English Civil War (1642–1651) in which CharlesI had been executed in 1649. He viewed the French revolution as the violent overthrow of a legitimate government. In "Reflections" he argues that citizens do not have the right to revolt against their government because civilization is the result of social and political consensus; its traditions cannot be continually challengedthe result would be anarchy. One of the key arguments of Wollstonecraft's "Rights of Men", published just six weeks after Burke's "Reflections", is that rights cannot be based on tradition; rights, she argues, should be conferred because they are reasonable and just, regardless of their basis in tradition.
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When Charles Maurice de Talleyrand-Périgord presented his "Rapport sur l'instruction publique" (1791) to the National Assembly in France, Wollstonecraft was galvanized to respond. In his recommendations for a national system of education, Talleyrand had written:
Let us bring up women, not to aspire to advantages which the Constitution denies them, but to know and appreciate those which it guarantees them... Men are destined to live on the stage of the world. A public education suits them: it early places before their eyes all the scenes of life: only the proportions are different. The paternal home is better for the education of women; they have less need to learn to deal with the interests of others, than to accustom themselves to a calm and secluded life.
Wollstonecraft dedicated the "Rights of Woman" to Talleyrand: "Having read with great pleasure a pamphlet which you have lately published, I dedicate this volume to you; to induce you to reconsider the subject, and maturely weigh what I have advanced respecting the rights of woman and national education." At the end of 1791, French feminist Olympe de Gouges had published her Declaration of the Rights of Woman and of the Female Citizen, and the question of women's rights became central to political debates in both France and Britain.
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The "Rights of Woman" is an extension of Wollstonecraft's arguments in the "Rights of Men". In the "Rights of Men", as the title suggests, she is concerned with the rights of particular men (eighteenth-century British men) while in the "Rights of Woman", she is concerned with the rights afforded to "woman", an abstract category. She does not isolate her argument to eighteenth-century women or British women. The first chapter of the "Rights of Woman" addresses the issue of natural rights and asks who has those inalienable rights and on what grounds. She answers that since natural rights are given by God, for one segment of society to deny them to another segment is a sin. "The Rights of Woman" thus engages not only specific events in France and in Britain but also larger questions being raised by political philosophers such as John Locke and Jean-Jacques Rousseau.
Themes.
The "Rights of Woman" is a long (almost 87,000 words) essay that introduces all of its major topics in the opening chapters and then repeatedly returns to them, each time from a different point of view. It also adopts a hybrid tone that combines rational argument with the fervent rhetoric of sensibility. Wollstonecraft did not employ the formal argumentation or logical prose style common to eighteenth-century philosophical writing.
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Hysteria was once seen as a physical phenomenonphysicians and anatomists believed that the more "sensitive" people's "nerves", the more emotionally affected they would be by their surroundings. Since women were thought to have keener nerves than men, it was believed that women were more emotional than men. The emotional excess associated with sensibility also theoretically produced an ethic of compassion: those with sensibility could easily sympathise with people in pain. Thus historians have credited the discourse of sensibility and those who promoted it with the increased humanitarian efforts, such as the movement to abolish the slave trade. But sensibility also paralysed those who had too much of it; as scholar G. J. Barker-Benfield explains, "an innate refinement of nerves was also identifiable with greater suffering, with weakness, and a susceptibility to disorder".
By the time Wollstonecraft was writing the "Rights of Woman", sensibility had already been under sustained attack for a number of years. Sensibility, which had initially promised to draw individuals together through sympathy, was now viewed as "profoundly separatist"; novels, plays, and poems that employed the language of sensibility asserted individual rights, sexual freedom, and unconventional familial relationships based only upon feeling. Furthermore, as Janet Todd, another scholar of sensibility, argues, "to many in Britain the cult of sensibility seemed to have feminized the nation, given women undue prominence, and emasculated men".
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Rational education.
One of Wollstonecraft's central arguments in the "Rights of Woman" is that women should be educated in a rational manner to give them the opportunity to contribute to society. In the eighteenth century, it was often assumed by educational philosophers and conduct book writers, who wrote what one might think of as early self-help books, that women were incapable of rational or abstract thought. Women, it was believed, were too susceptible to sensibility and too fragile to be able to think clearly. Wollstonecraft, along with other female reformers such as Catharine Macaulay and Hester Chapone, maintained that women were indeed capable of rational thought and deserved to be educated. She argued this point in her own conduct book, "Thoughts on the Education of Daughters" (1787), in her children's book, "Original Stories from Real Life" (1788), as well as in the "Rights of Woman".
Stating in her preface that "my main argument is built on this simple principle, that if [woman] be not prepared by education to become the companion of man, she will stop the progress of knowledge and virtue; for truth must be common to all", Wollstonecraft contends that society will degenerate without educated women, particularly because mothers are the primary educators of young children. She attributes the problem of uneducated women to men and "a false system of education, gathered from the books written on this subject by men who [consider] females rather as women than human creatures". Women are capable of rationality; it only appears that they are not, because men have refused to educate them and encouraged them to be frivolous (Wollstonecraft describes silly women as "spaniels" and "toys").
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Wollstonecraft attacks conduct book writers such as James Fordyce and John Gregory as well as educational philosophers such as Jean-Jacques Rousseau who argue that a woman does not need a rational education. (Rousseau argues in "" [1762] that women should be educated for the pleasure of men; Wollstonecraft, infuriated by this argument, attacks not only it but also Rousseau himself.) Intent on illustrating the limitations that contemporary educational theory placed upon women, Wollstonecraft writes, "taught from their infancy that beauty is woman's sceptre, the mind shapes itself to the body, and, roaming round its gilt cage, only seeks to adorn its prison", implying that without this damaging ideology, which encourages young women to focus their attention on beauty and outward accomplishments, they could achieve much more. Wives could be the rational "companions" of their husbands and even pursue careers should they so choose: "women might certainly study the art of healing, and be physicians as well as nurses. And midwifery, decency seems to allot to them... they might, also, study politics... Business of various kinds, they might likewise pursue."
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For Wollstonecraft, "the most perfect education" is "an exercise of the understanding as is best calculated to strengthen the body and form the heart. Or, in other words, to enable the individual to attach such habits of virtue as will render it independent." In addition to her broad philosophical arguments, Wollstonecraft lays out a specific plan for national education to counter Talleyrand's. In Chapter 12, "On National Education", she proposes that children be sent to free day schools as well as given some education at home "to inspire a love of home and domestic pleasures". She also maintains that schooling should be co-educational, contending that men and women, whose marriages are "the cement of society", should be "educated after the same model".
Feminism.
It is debatable to what extent the "Rights of Woman" is a feminist text; because the definitions of "feminist" vary, different scholars have come to different conclusions. The words "feminist" and "feminism" were not coined until the 1890s, and there was no feminist movement to speak of during Wollstonecraft's lifetime. "Rights of Woman" is often considered the source or original, "the ur-document of modern liberal feminism". In the introduction to her work on Wollstonecraft's thought, Barbara Taylor writes:
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Describing [Wollstonecraft's philosophy] as feminist is problematic, and I do it only after much consideration. The label is of course anachronistic... Treating Wollstonecraft's thought as an anticipation of nineteenth and twentieth-century feminist argument has meant sacrificing or distorting some of its key elements. Leading examples of this... have been the widespread neglect of her religious beliefs, and the misrepresentation of her as a bourgeois liberal, which together have resulted in the displacement of a religiously inspired utopian radicalism by a secular, class-partisan reformism as alien to Wollstonecraft's political project as her dream of a divinely promised age of universal happiness is to our own. Even more important however has been the imposition on Wollstonecraft of a heroic-individualist brand of politics utterly at odds with her own ethically driven case for women's emancipation. Wollstonecraft's leading ambition for women was that they should attain virtue, and it was to this end that she sought their liberation.
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In the "Rights of Woman", Wollstonecraft does not make the claim for gender equality using the same arguments or the same language that late nineteenth- and twentieth-century feminists later would. For instance, rather than unequivocally stating that men and women are equal, Wollstonecraft contends that men and women are equal in the eyes of God, which means that they are both subject to the same moral law. For Wollstonecraft, men and women are equal in the most important areas of life. While such an idea may not seem revolutionary to twenty-first-century readers, its implications were revolutionary during the eighteenth century. For example, it implied that both men and womennot just womenshould be modest and respect the sanctity of marriage. Wollstonecraft's argument exposed the sexual double standard of the late eighteenth century and demanded that men adhere to the same virtues demanded of women.
However, Wollstonecraft's arguments for equality stand in contrast to her statements respecting the superiority of masculine strength and valour. Wollstonecraft states:
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Let it not be concluded, that I wish to invert the order of things; I have already granted, that, from the constitution of their bodies, men seem to be designed by Providence to attain a greater degree of virtue. I speak collectively of the whole sex; but I see not the shadow of a reason to conclude that their virtues should differ in respect to their nature. In fact, how can they, if virtue has only one eternal standard? I must therefore, if I reason consequentially, as strenuously maintain that they have the same simple direction, as that there is a God.
Wollstonecraft calls on men, rather than women, to initiate the social and political changes she outlines in the "Rights of Woman". Because women are uneducated, they cannot alter their own situationmen must come to their aid. Wollstonecraft writes at the end of her chapter "Of the Pernicious Effects Which Arise from the Unnatural Distinctions Established in Society":
I then would fain convince reasonable men of the importance of some of my remarks; and prevail on them to weigh dispassionately the whole tenor of my observations... I appeal to their understandings; and, as a fellow-creature, claim, in the name of my sex, some interest in their hearts. I entreat them to assist to emancipate their companion, to make her a help meet for them! Would men but generously snap our chains, and be content with rational fellowship instead of slavish obedience, they would find us more observant daughters, more affectionate sisters, more faithful wives, more reasonable mothersin a word, better citizens.
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Wollstonecraft's last novel, "" (1798), the fictionalized sequel to the "Rights of Woman", is usually considered her most radical feminist work.
Sensibility.
One of Wollstonecraft's most scathing criticisms in the "Rights of Woman" is against false and excessive sensibility, particularly in women. She argues that women who succumb to sensibility are "blown about by every momentary gust of feeling"; because these women are "the prey of their senses", they cannot think rationally. Not only do they do harm to themselves but they also do harm to all of civilization: these are not women who can refine civilizationthese are women who will destroy it. But reason and feeling are not independent for Wollstonecraft; rather, she believes that they should inform each other. For Wollstonecraft the passions underpin all reason. This was a theme that she would return to throughout her career, but particularly in her novels ' (1788) and '. For the eighteenth-century Scottish philosopher David Hume, reason is dominated by the passions. He held that passions rather than reason govern human behaviour, famously proclaiming in "A Treatise of Human Nature" that "Reason is, and ought only to be the slave of the passions".
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As part of her argument that women should not be overly influenced by their feelings and emotions, Wollstonecraft emphasises that they should not be constrained by or made slaves to their bodies or their sexual feelings. This particular argument has led many modern feminists to suggest that Wollstonecraft intentionally avoids granting women any sexual desire. Cora Kaplan argues that the "negative and prescriptive assault on female sexuality" is a leitmotif of the "Rights of Woman". For example, Wollstonecraft advises her readers to "calmly let passion subside into friendship" in the ideal companionate marriage (that is, in the ideal of a love-based marriage that was developing at the time). It would be better, she writes, when "two virtuous young people marry . . . if some circumstances checked their passion". According to Wollstonecraft, "love and friendship cannot subsist in the same bosom". As Mary Poovey explains, "Wollstonecraft betrays her fear that female desire might in fact court man's lascivious and degrading attentions, that the subordinate position women have been given might even be deserved.
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"Wollstonecraft betrays her fear that female desire might in fact court man's lascivious and degrading attentions, that the subordinate position women have been given might even be deserved. Until women can transcend their fleshly desires and fleshly forms, they will be hostage to the body." If women are not interested in sexuality, they cannot be dominated by men. Wollstonecraft worries that women are consumed with "romantic wavering", that is, they are interested only in satisfying their lusts. Because the "Rights of Woman" eliminates sexuality from a woman's life, Kaplan contends, it "expresses a violent antagonism to the sexual" while at the same time "exaggerat[ing] the importance of the sensual in the everyday life of women". Wollstonecraft was so determined to wipe sexuality from her picture of the ideal woman that she ended up foregrounding it by insisting upon its absence. But as Kaplan and others have remarked, Wollstonecraft may have been forced to make this sacrifice: "it is important to remember that the notion of woman as politically enabled and independent [was] fatally linked [during the eighteenth century] to the unrestrained and vicious exercise of her sexuality."
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Republicanism.
Claudia Johnson, a prominent Wollstonecraft scholar, has called the "Rights of Woman" "a republican manifesto". Johnson contends that Wollstonecraft is hearkening back to the Commonwealth tradition of the seventeenth century and attempting to reestablish a republican ethos. In Wollstonecraft's version, there would be strong, but separate, masculine and feminine roles for citizens. According to Johnson, Wollstonecraft "denounces the collapse of proper sexual distinction as the leading feature of her age, and as the grievous consequence of sentimentality itself. The problem undermining society in her view is feminized men". If men feel free to adopt both the masculine position and the sentimental feminine position, she argues, women have no position open to them in society. Johnson therefore sees Wollstonecraft as a critic, in both the "Rights of Men" and the "Rights of Woman", of the "masculinization of sensitivity" in such works as Edmund Burke's "Reflections on the Revolution in France".
In the "Rights of Woman" Wollstonecraft adheres to a version of republicanism that includes a belief in the eventual overthrow of all titles, including the monarchy. She also suggests that all men and women should be represented in government. But the bulk of her "political criticism", as Chris Jones, a Wollstonecraft scholar, explains, "is couched predominantly in terms of morality". Her definition of virtue focuses on the individual's happiness rather than, for example, the good of society. This is reflected in her explanation of natural rights. Because rights ultimately proceed from God, Wollstonecraft maintains that there are duties, tied to those rights, incumbent upon each and every person. For Wollstonecraft, the individual is taught republicanism and benevolence within the family; domestic relations and familial ties are crucial to her understanding of social cohesion and patriotism.
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Class.
In many ways the "Rights of Woman" is inflected by a bourgeois view of the world, as is its direct predecessor the "Rights of Men". Wollstonecraft addresses her text to the middle class, which she calls the "most natural state". She also frequently praises modesty and industry, virtues which, at the time, were associated with the middle class. From her position as a middle-class writer arguing for a middle-class ethos, Wollstonecraft also attacks the wealthy, criticizing them using the same arguments she employs against women. She points out the "false-refinement, immorality, and vanity" of the rich, calling them "weak, artificial beings, raised above the common wants and affections of their race, in a premature unnatural manner [who] undermine the very foundation of virtue, and spread corruption through the whole mass of society".
But Wollstonecraft's criticisms of the wealthy do not necessarily reflect a concomitant sympathy for the poor. For her, the poor are fortunate because they will never be trapped by the snares of wealth: "Happy is it when people have the cares of life to struggle with; for these struggles prevent their becoming a prey to enervating vices, merely from idleness!" She contends that charity has only negative consequences because, as Jones puts it, she "sees it as sustaining an unequal society while giving the appearance of virtue to the rich".
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In her national plan for education, she retains class distinctions (with an exception for the intelligent), suggesting that: "After the age of nine, girls and boys, intended for domestic employments, or mechanical trades, ought to be removed to other schools, and receive instruction, in some measure appropriated to the destination of each individual... The young people of superior abilities, or fortune, might now be taught, in another school, the dead and living languages, the elements of science, and continue the study of history and politics, on a more extensive scale, which would not exclude polite literature."
Rhetoric and style.
In attempting to navigate the cultural expectations of female writers and the generic conventions of political and philosophical discourse, Wollstonecraft, as she does throughout her "oeuvre", constructs a unique blend of masculine and feminine styles in the "Rights of Woman". She uses the language of philosophy, referring to her work as a "treatise" with "arguments" and "principles". However, Wollstonecraft also uses a personal tone, employing "I" and "you", dashes and exclamation marks, and autobiographical references to create a distinctly feminine voice in the text. The "Rights of Woman" further hybridizes its genre by weaving together elements of the conduct book, the short essay, and the novel, genres often associated with women, while at the same time claiming that these genres could be used to discuss philosophical topics such as rights.
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Although Wollstonecraft argues against excessive sensibility, the rhetoric of the "Rights of Woman" is at times heated and attempts to provoke the reader. Many of the most emotional comments in the book are directed at Rousseau. For example, after excerpting a long passage from "" (1762), Wollstonecraft pithily states, "I shall make no other comments on this ingenious passage, than just to observe, that it is the philosophy of lasciviousness." A mere page later, after indicting Rousseau's plan for female education, she writes "I must relieve myself by drawing another picture." These terse exclamations are meant to draw the reader to her side of the argument (it is assumed that the reader will agree with them). While she claims to write in a plain style so that her ideas will reach the broadest possible audience, she actually combines the plain, rational language of the political treatise with the poetic, passionate language of sensibility to demonstrate that one can combine rationality and sensibility in the same self.
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In her efforts to vividly describe the condition of women within society, Wollstonecraft employs several different analogies. She often compares women to slaves, arguing that their ignorance and powerlessness places them in that position. But at the same time, she also compares them to "capricious tyrants" who use cunning and deceit to manipulate the men around them. At one point, she reasons that a woman can become either a slave or tyrant, which she describes as two sides of the same coin. Wollstonecraft also compares women to soldiers; like military men, they are valued only for their appearance and obedience. And like the rich, women's "softness" has "debased mankind".
Revision.
Wollstonecraft was forced to write the "Rights of Woman" hurriedly to respond to Talleyrand and ongoing events. Upon completing the work, she wrote to her friend William Roscoe: "I am dissatisfied with myself for not having done justice to the subject... Do not suspect me of false modestyI mean to say that had I allowed myself more time I could have written a better book, in every sense of the word... I intend to finish the next volume before I begin to print, for it is not pleasant to have the Devil coming for the conclusion of a sheet fore it is written." When Wollstonecraft revised the "Rights of Woman" for the second edition, she took the opportunity not only to fix small spelling and grammar mistakes but also to bolster the feminist claims of her argument. She changed some of her statements regarding female and male difference to reflect a greater equality between the sexes.
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Wollstonecraft never wrote the second part to the "Rights of Woman," although William Godwin published her "Hints", which were "chiefly designed to have been incorporated in the second part of the "Vindication of the Rights of Woman", in the posthumous collection of her works. However, she did begin writing the novel ", which most scholars consider a fictionalized sequel to the "Rights of Woman". It was unfinished at her death and also included in the "Posthumous Works" published by Godwin.
Reception and legacy.
When it was first published in 1792, the "Rights of Woman" was reviewed favourably by the "Analytical Review", the "General Magazine", the "Literary Magazine", "New York Magazine", and the "Monthly Review", although the assumption persists that "Rights of Woman" received hostile reviews. It was almost immediately released in a second edition in 1792, several American editions appeared, and it was translated into French. Taylor writes that "it was an immediate success". Moreover, other writers such as Mary Hays and Mary Robinson specifically alluded to Wollstonecraft's text in their own works. Hays cited the "Rights of Woman" in her novel "Memoirs of Emma Courtney" (1796) and modelled her female characters after Wollstonecraft's ideal woman.
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Although female conservatives such as Hannah More excoriated Wollstonecraft personally, they actually shared many of the same values. As the scholar Anne Mellor has shown, both More and Wollstonecraft wanted a society founded on "Christian virtues of rational benevolence, honesty, personal virtue, the fulfillment of social duty, thrift, sobriety, and hard work". During the early 1790s, many writers within British society were engaged in an intense debate regarding the position of women in society. For example, the respected poet and essayist Anna Laetitia Barbauld and Wollstonecraft sparred back and forth; Barbauld published several poems responding to Wollstonecraft's work and Wollstonecraft commented on them in footnotes to the "Rights of Woman". The work also provoked outright hostility. The bluestocking Elizabeth Carter was unimpressed with the work. Thomas Taylor, the Neoplatonist translator who had been a landlord to the Wollstonecraft family in the late 1770s, swiftly wrote a satire called "A Vindication of the Rights of Brutes": if women have rights, why not animals too?
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After Wollstonecraft died in 1797, her husband William Godwin published his "Memoirs of the Author of A Vindication of the Rights of Woman" (1798). He revealed much about her private life that had previously not been known to the public: her illegitimate child, her love affairs, and her attempts at suicide. While Godwin believed he was portraying his wife with love, sincerity, and compassion, contemporary readers were shocked by Wollstonecraft's unorthodox lifestyle and she became a reviled figure. Richard Polwhele targeted her in particular in his anonymous long poem "The Unsex'd Females" (1798), a defensive reaction to women's literary self-assertion: Hannah More is Christ to Wollstonecraft's Satan. His poem was "well known" among the responses to "A Vindication".
Wollstonecraft's ideas became associated with her life story and women writers felt that it was dangerous to mention her in their texts. Hays, who had previously been a close friend and an outspoken advocate for Wollstonecraft and her "Rights of Woman", for example, did not include her in the collection of "Illustrious and Celebrated Women" she published in 1803. Maria Edgeworth specifically distances herself from Wollstonecraft in her novel "Belinda" (1802); she caricatures Wollstonecraft as a radical feminist in the character of Harriet Freke. But, like Jane Austen, she does not reject Wollstonecraft's ideas. Both Edgeworth and Austen argue that women are crucial to the development of the nation; moreover, they portray women as rational beings who should choose companionate marriage.
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The negative views towards Wollstonecraft persisted for over a century. The "Rights of Woman" was not reprinted until the middle of the nineteenth century and it still retained an aura of ill-repute. George Eliot wrote "there is in some quarters a vague prejudice against the "Rights of Woman" as in some way or other a reprehensible book, but readers who go to it with this impression will be surprised to find it eminently serious, severely moral, and withal rather heavy". The suffragist (i.e. moderate reformer, as opposed to suffragette) Millicent Garrett Fawcett wrote the introduction to the centenary edition of the "Rights of Woman", cleansing the memory of Wollstonecraft and claiming her as the foremother of the struggle for the vote. While the "Rights of Woman" may have paved the way for feminist arguments, twentieth-century feminists have tended to use Wollstonecraft's life story, rather than her texts, for inspiration; her unorthodox lifestyle convinced them to try new "experiments in living", as Virginia Woolf termed it in her famous essay on Wollstonecraft.
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While the "Rights of Woman" may have paved the way for feminist arguments, twentieth-century feminists have tended to use Wollstonecraft's life story, rather than her texts, for inspiration; her unorthodox lifestyle convinced them to try new "experiments in living", as Virginia Woolf termed it in her famous essay on Wollstonecraft. However, there is some evidence that the "Rights of Woman" may be influencing current feminists. Ayaan Hirsi Ali, a feminist who is critical of Islam's dictates regarding women, cites the "Rights of Woman" in her autobiography "Infidel", writing that she was "inspired by Mary Wollstonecraft, the pioneering feminist thinker who told women they had the same ability to reason as men did and deserved the same rights". Miriam Schneir also includes this text in her anthology "", labelling it as one of the essential feminist works.
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the pioneering feminist thinker who told women they had the same ability to reason as men did and deserved the same rights". Miriam Schneir also includes this text in her anthology "", labelling it as one of the essential feminist works. In "Death Comes to Pemberley" (2011), set in 1803, P. D. James has one male character reference "Rights of Woman" in reproving another (Darcy) for denying voice to the woman in matters that concern her.
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Afghan Hound
The Afghan Hound is a hound distinguished by its thick, fine, silky coat, and a tail with a ring curl at the end. The breed originates in the cold mountains of Afghanistan. Its local name is ( ) or ( ). Other names for this breed are Tāzī, Balkh Hound, Baluchi Hound, and Barakzai Hound.
The American Kennel Club (AKC) describes the breed as among the most eye-catching of all. The Afghan Hound is an "aloof and dignified aristocrat of sublime beauty." Despite their regal appearance, the Afghan possesses an "endearing streak of silliness and a profound loyalty."
Admired since ancient times for their beauty, the Afghan Hound's distinctive coat was developed as protection from the harsh mountain climate. Their huge paw-pads served as shock absorbers on the rocky terrain.
History.
The Afghan Hound has been identified as a basal breed that predates the emergence of the modern breeds in the 19th century. It is most closely related to the Saluki.
Connections with other types and breeds from the same area may provide clues to the history. A name for a desert coursing Afghan Hound, Tazi (Sag-e-Tazi), suggests a shared ancestry with the very similar Tazy breed from the Caspian Sea area of Russia and Turkmenistan. Other types or breeds of similar appearance are the Taigan from the mountainous Tian Shan region on the Chinese border of Afghanistan, and the Barakzay, or Kurram Valley Hound.
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Once out of Afghanistan, the history of the Afghan Hound breed became entwined with that of the very earliest dog shows and the Kennel Club (UK). Various sighthounds were brought to England in the 1800s by army officers returning from British India and were exhibited at dog shows, which were then just becoming popular, under various names, such as Barukzy hounds. They were also called "Persian Greyhounds" by the English, in reference to their own indigenous sighthound.
One dog in particular, Zardin, was brought in 1907 from India by Captain John Barff. Zardin became the early ideal for the breed type still referred to as the Persian Greyhound. Zardin was the basis of the writing for the first breed standard in 1912, but this breeding cycle was stopped by World War I.
Out of the longhaired sighthound types known in Afghanistan, two main strains make up the modern Afghan Hound breed. The first were a group of hounds brought to Scotland from Balochistan by Major and Mrs. G. Bell-Murray and Miss Jean C. Manson in 1920, and they are known as the Bell-Murray strain. These dogs were of the "steppe" or “desert” type and were less heavily coated.
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The second strain was a group of dogs from a kennel in Kabul owned by Mrs. Mary Amps, which she shipped to England in 1925. She and her husband came to Kabul after the Afghan war in 1919, and the foundation sire of her kennel (named Ghazni) in Kabul was a dog that closely resembled Zardin. Her Ghazni strain were the more heavily coated mountain type. Most of the Afghans in the United States were developed from the Ghazni strain from England. The first Afghans in Australia were imported from the United States in 1934, also of the Ghazni strain. The mountain and steppe strains became mixed into the modern Afghan Hound breed, and a new standard was written in 1948, which is still used today.
The Afghan Hound can also come with a much more "patterned" coat. This descends from the Bell-Murray's and the Ghazni lines, and is displayed in much lighter feathering of coat, deeper saddle (often actually looking like a saddle) and much shorter hair on the face and neck. It is believed that these particular Afghan Hounds were a product of much hotter parts of the country.
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The beauty of Afghan Hound dogs caused them to become highly desirable show dogs and pets, and they are recognised by all of the major kennel clubs in the English-speaking world. One of the Amps Ghazni, Sirdar, won best in show at Crufts in 1928 and 1930. An Afghan Hound was featured on the cover of Life Magazine on November 26, 1945. Afghan Hounds were the most popular in Australia in the 1970s, and won most of the major shows. An Afghan Hound won Best in Show (BIS) at the 1996 World Dog Show in Budapest. Afghan Hounds were BIS at the Westminster Kennel Club Dog Show in 1957 and again in 1983.
The Afghan Hound breed is no longer used for hunting, although it can be seen in the sport of lure coursing.
On August 3, 2005, Korean scientist Hwang Woo-Suk announced that his team of researchers had become the first team to successfully clone a dog, an Afghan Hound named Snuppy. In 2006 Hwang Woo-Suk was dismissed from his university position for fabricating data in his research. Snuppy, nonetheless, was a genuine clone, and thus the first cloned dog in history.
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Description.
The dogs in this breed occur in many different coat colors. A study that mapped the genes of Afghan Hounds and discussed the effect of genes on coat colour in the breed was published in the Journal of Heredity in 2010.
The Afghan Hound is tall, standing in height and weighing . The coat may be any colour, but white markings, particularly on the head, are discouraged; many individuals have a black facial mask. A specimen may have a beard on the lower jaw, known as a "mandarin". Some Afghan Hounds are almost white, but parti-color hounds (white with islands of red or black) are penalized in the AKC standard, but not by the FCI.
Their long, fine-textured coat requires considerable care and grooming. The long topknot and the shorter-haired saddle on the back of the dog are distinctive features of the Afghan Hound coat. The high hipbones and unique small ring on the end of the tail are also characteristics of the breed.
The temperament of the typical Afghan Hound can be aloof and dignified, but happy and clownish when playing. This breed, as tends to be the case with sighthounds, has a high prey drive and may kill small animals and livestock. Genomic studies have pointed to the Afghan Hound as one of the oldest of dog breeds.
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The breed has a reputation among dog trainers of having a relatively slow "obedience intelligence"; Stanley Coren, in his book "The Intelligence of Dogs", ranked the breed last among 138 breeds mentioned in ability to understand and obey commands, requiring more than 80 repetitions to understand a new command and obeying on the first command less than 25% of the time. Coren noted that Afghan Hounds were consistently ranked among the least obedient dog breeds among all of the trainers he consulted, with a majority (121 out of 199) ranking the Afghan Hound in the lowest ten breeds out of 133 listed.
Variants.
Khalag Tazi.
The Khalag Tazi is a variety of the Afghan Hound introduced to Europe in 1920, when an Indian Army officer, Major G Bell-Murray, brought some animals back from Afghanistan.
Bakhmull.
Bakhmull (also Bakhmull Tazi or Tazi Bakhmull, also called the Aboriginal Afghan Hound) is a long-haired variety of sighthound. It has been bred mostly in Russia and claimed to represent an Afghan Hound aboriginal to Afghanistan. In Pashto the word means "velvet", applied in reference to the dog's silky coat, which is rather abundant and long on the whole body, except the "saddle" (middle to lower back), front parts of all four legs, and the muzzle. Its color is always fawn, ivory, or white, with a darker "saddle", thus it produces an impression of a (yellowish) dog whose coat color matches the khaki sandstone and limestone of the Hindu Kush mountain landscape and deserts. The following colors are not permissible: red, red with white spots, black, and black with white spots.
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Since the 1980s, the centre of Bakhmull breeding has been Russia, beginning in Moscow, then spreading to various other places in the CIS. The foundation stock was brought to Russia in the 1970s by military men returning from Afghanistan. Natalia Gherasiova (a breeder, of the Blue Dale el Bark Bakhmull kennel, and dog show judge) established the National Bakhmull Club, affiliated with the Russian Federation for Hunting Dogs (RFOS) and Russian Kynological Federation (RKF). A breed standard was first published in 1985, and a shared RFOS–RKF revision was produced in 1997.
Bakhmulls hunt solo and in couples. Although its coat is long, it does not require much grooming. Paws are well protected from injuries by "feathering" (thick additional paw fur). Its long, velvety coat and its stamina makes more suitable than many breeds for harsh weather. The breed standard calls for "aristocratic gait and a beautiful head with gazelle-like ... eyes". The eyes should be large, brown, slanting upwards, and of almond shape, with rims outlined black. Black coloration is required on the nose and lips for both white and fawn bakhmulls. The dog's height should be between , for bitches. The height at the withers is higher than at the croup.
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Health.
Lifespan.
A UK study found a life expectancy of 11.1 years for the breed compared to an average of 12.7 for purebreeds and 12 for crossbreeds.
Health concerns.
Major health issues are allergies, cancer, and hip dysplasia. Like other sighthounds, the Afghan Hound is sensitive to anesthesia, as sighthounds have relatively low levels of body fat. Afghan Hounds are also among the dog breeds most likely to develop chylothorax, a rare condition which causes the thoracic ducts to leak, allowing large quantities of chyle fluid to enter the dog's chest cavity. This condition commonly results in a lung-lobe torsion (in which the dog's lung twists within the chest cavity, requiring emergency surgery), due to the breed's typically deep, "barrel"-shaped chest. If not corrected through surgery, chylothorax can ultimately cause fibrosing pleuritis, or a hardening of the organs, due to scar tissue forming around the organs to protect them from the chyle fluid. Chylothorax is often fatal.
Among other health problems are laryngeal paralysis, dilated cardiomyopathy (twice as common in males as females), and dermatological issues such as testosterone-responsive dermatosis of male dogs (often seen in castrated males), nasal depigmentation (also known as Dudley nose), and skin tumours. Afghans are also prone to Central diabetes insipidus (CDI), hypothyroidism and tricholemmoma, a rare condition which mainly affects older dogs in the Middle Ages. Ocular conditions that can occur include medial canthal pocket syndrome (breed predisposition due to shape of head), corneal dystrophy, cataract and generalized progressive retinal atrophy (GPRA). Afghan myelopathy (causing pelvic limb ataxia) is sometimes reported.
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In popular culture.
Pablo Picasso said that his 1967 statue located in Chicago's Daley Plaza represented the head of an Afghan Hound named Kabul.
The Afghan Hound has been represented in multiple animated feature films and TV shows, including Universal Pictures' "Balto" (Sylvie), Disney's "" (Ruby), Hasbro Studios's "Pound Puppies" (Twiggy) and ABC Kids' "Bluey" (Indy). An Afghan Hound also appeared in the films "One Hundred and One Dalmatians," "101 Dalmatians," "102 Dalmatians, and ". Other examples include Prince Amir of Kinjan from "What-a-Mess," Persia from "Road Rovers," Burt from "Foofur," Laila from "Roadside Romeo," and Brainy Barker from "Krypto the Superdog". Malory Archer in the show "Archer" also had an Afghan Hound named Duchess at some point in her childhood.
In the 1941 novel "Between the Acts", Virginia Woolf uses an Afghan Hound named Sohrab to represent aspects of one of the book's human characters.
The Afghan Hound features prominently in the avant-garde music video of French band M83's, "Set in Stone (M83 Remix)".
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Azawakh
The Azawakh is a breed of dog from West Africa. With ancient origins, it is raised throughout the Sahelian zone of Mali, Niger, and Burkina Faso. This region includes the Azawagh Valley for which the breed is named. While commonly associated with the nomadic Tuareg people, the dogs are also bred and owned by other ethnic groups, such as the Peulh, Bella, and Hausa. The Azawakh is more related to the Sloughi than it is to the Saluki.
Description.
Appearance.
Slim and elegant, with bone structure and muscles showing through thin skin. Eyes are almond-shaped.
The coat is very short and almost absent on the belly. Its bone structure shows clearly through the skin and musculature. Its muscles are "dry", meaning that they are quite flat, unlike the Greyhound and Whippet. In this respect it is similar in type to the Saluki.
Colours.
Colours permitted by the Fédération Cynologique Internationale (FCI) breed standard are clear sand to dark fawn/brown, red and brindle (with or without a dark mask), with white bib, tail tip, and white on all feet (which can be tips of toes to high stockings). Since 2015 white stockings that go above the elbow joint are considered disqualifying features in the FCI member countries, as is a white collar or half collar (Irish marked).
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Some conservationists support the idea that in Africa, Azawakhs are still found in a variety of colours such as red, blue fawn (that is, with a lilac cast), grizzle, and, rarely, blue and black with various white markings including Irish marked (white collar) and particolour (mostly white). Because of this wide color variation in the native population, the American standard used by the AKC and UKC allows any color combination found in Africa.
Movement.
The Azawakh's light, supple, lissome gait is a notable breed characteristic, as is an upright double suspension gallop.
Temperament.
Bred by the Tuareg, Fula and various other nomads of the Sahara and sub-Saharan Sahel in the countries of Mali, Niger, Burkina Faso, and southern Algeria, the breed known by the Tuaregs as ”Oska” was used there as a guard dog and to hunt gazelle and hare at speeds up to . The austerity of the Sahel environment has ensured that only the most fit dogs survive and has accentuated the breed's ruggedness and independence. Unlike some other sighthounds, the Azawakh is more of a pack hunter and they bump down the quarry with hindquarters when it has been tired out. In role of a guard dog, if an Azawakh senses danger it will bark to alert the other members of the pack, and they will gather together as a pack under the lead of the alpha dog, then chase off or attack the predator.
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Unlike other sighthounds, the primary function of the Azawakh in its native land is that of a guard dog. It develops an intense bond with its owner, and tend to be reserved with strangers.
Azawakh have high energy and tremendous endurance. They are excellent training companions for runners. Many Azawakh dislike rain and cold weather.
Azawakh are pack oriented and form complex social hierarchies. They have tremendous memories and are able to recognize each other after long periods of separation. They can often be found sleeping on top of each other for warmth and companionship.
Breed history.
The breed is relatively uncommon in Europe and North America but there is a growing band of devotees. Azawakh may be registered with the FCI in the USA via the Federación Canófila de Puerto Rico (FCPR). European FCI clubs and the AKC recognize the FCPR as an acceptable registry. The AKC recognized the Azawakh a member of the Hound group in 2019. The American Azawakh Association (AAA) is the AKC Parent Club for the Azawakh. Azawakh may be registered with the UKC and ARBA. The breed is not yet registered by CKC. Azawakh are eligible for ASFA and AKC lure coursing and NOFCA open field coursing events.
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Acrylic paint
Acrylic paint is a fast-drying paint made of pigment suspended in acrylic polymer emulsion and plasticizers, silicone oils, defoamers, stabilizers, or metal soaps. Most acrylic paints are water-based, but become water-resistant when dry. Depending on how much the paint is diluted with water, or modified with acrylic gels, mediums, or pastes, the finished acrylic painting can resemble a watercolor, a gouache, or an oil painting, or it may have its own unique characteristics not attainable with other media.
Water-based acrylic paints are used as latex house paints, as latex is the technical term for a suspension of polymer microparticles in water. Interior latex house paints tend to be a combination of binder (sometimes acrylic, vinyl, PVA, and others), filler, pigment, and water. Exterior latex house paints may also be a co-polymer blend, but the best exterior water-based paints are 100% acrylic, because of its elasticity and other factors. Vinyl, however, costs half of what 100% acrylic resins cost, and polyvinyl acetate (PVA) is even cheaper, so paint companies make many different combinations of them to match the market.
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History.
German chemist Otto Röhm invented acrylic resin, which led to the development of acrylic paint. In 1934, the first usable acrylic resin dispersion was developed by German chemical company BASF, and patented by Rohm and Haas. The synthetic paint was first used in the 1940s, displaying some properties of both oil and watercolor. Between 1946 and 1949, Leonard Bocour and Sam Golden invented a solution acrylic paint under the brand Magna paint. These were mineral spirit-based paints.
Water-based acrylic paints were subsequently sold as latex house paints.
Soon after the water-based acrylic binders were introduced as house paints, both individual artists and companies began to explore the new binders. Mexican mural painters like Diego Rivera, David Alfaro Siqueiros, and José Clemente Orozco were among the first to experiment with acrylic paint, impressed with its durability. Politec Acrylic Artists' Colors, water based acrylics useful for mural painting, started being produced and distributed in Mexico in 1953 by both individuals and companies. These acrylic paints began to phase out oil paint in mural art and abstract expressionism.
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Over the 1960s Lancelot Ribeiro pioneered the use of acrylic paints for art in the UK because of his "increasing impatience" of the time it took for oil paints to dry, as also its "lack of brilliance in its colour potential." He took to the new synthetic plastic bases that commercial paints were beginning to use and soon got help from manufacturers like ICI, Courtaulds, and Geigy. The companies supplied him samples of their latest paints in quantities that he was using three decades later, according to the paper. Initially, the firms thought the PVA compounds would not be needed in commercially viable quantities. But they quickly recognised the potential demand and "so Ribeiro became the godfather of generations of artists using acrylics as an alternative to oils."
In 1956, José L. Gutiérrez produced "Politec Acrylic Artists' Colors" in Mexico, and Henry Levison of Cincinnati-based Permanent Pigments Co. produced Liquitex colors. These two product lines were the first acrylic emulsion artists' paints, with modern high-viscosity paints becoming available in the early 1960s.
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Painting with acrylics.
Acrylic painters can modify the appearance, hardness, flexibility, texture, and other characteristics of the paint surface by using acrylic medium or simply by adding water. Watercolor and oil painters also use various mediums, but the range of acrylic mediums is much greater. Acrylics have the ability to bond to many different surfaces, and mediums can be used to modify their binding characteristics. Acrylics can be used on paper, canvas, and a range of other materials; however, their use on engineered woods such as medium-density fiberboard can be problematic because of the porous nature of those surfaces. In these cases, it is recommended that the surface first be sealed with an appropriate sealer. The process of sealing acrylic painting is called varnishing. Artists use removable varnishes over isolation coat to protect paintings from dust, UV, scratches, etc. This process is similar to varnishing an oil painting.
Acrylics can be applied in thin layers or washes to create effects that resemble watercolors and other water-based mediums. They can also be used to build thick layers of paint — gel and molding paste are sometimes used to create paintings with relief features. Acrylic paints are also used in hobbies such as trains, cars, houses, DIY projects, and human models. People who make such models use acrylic paint to build facial features on dolls or raised details on other types of models. Wet acrylic paint is easily removed from paintbrushes and skin with water, whereas oil paints require the use of a hydrocarbon.
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Acrylics are the most common paints used in grattage, a surrealist technique that began to be used with the advent of this type of paint. Acrylics are used for this purpose because they easily scrape or peel from a surface.
Painting techniques.
Acrylic artists' paints may be thinned with water or acrylic medium and used as washes in the manner of watercolor paints, but unlike watercolor the washes are not rehydratable once dry. For this reason, acrylics do not lend themselves to the color lifting techniques of gum arabic-based watercolor paints. Instead, the paint is applied in layers, sometimes diluting with water or acrylic medium to allow layers underneath to partially show through. Using an acrylic medium gives the paint more of a rich and glossy appearance, whereas using water makes the paint look more like watercolor and have a matte finish.
Acrylic paints with gloss or matte finishes are common, although a satin (semi-matte) sheen is most common. Some brands exhibit a range of finishes (e.g. heavy-body paints from Golden, Liquitex, Winsor & Newton and Daler-Rowney); Politec acrylics are fully matte. As with oils, pigment amounts and particle size or shape can affect the paint sheen. Matting agents can also be added during manufacture to dull the finish. If desired, the artist can mix different media with their paints and use topcoats or varnishes to alter or unify sheen.
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When dry, acrylic paint is generally non-removable from a solid surface if it adheres to the surface. Water or mild solvents do not re-solubilize it, although isopropyl alcohol can lift some fresh paint films off. Toluene and acetone can remove paint films, but they do not lift paint stains very well and are not selective. The use of a solvent to remove paint may result in removal of all of the paint layers (acrylic gesso, et cetera). Oils and warm, soapy water can remove acrylic paint from skin. Acrylic paint can be removed from nonporous plastic surfaces such as miniatures or models using cleaning products such as Dettol (containing chloroxylenol 4.8% v/w).
An acrylic sizing should be used to prime canvas in preparation for painting with acrylic paints, to prevent Support Induced Discoloration (SID). Acrylic paint contains surfactants that can pull up discoloration from a raw canvas, especially in transparent glazed or translucent gelled areas. Gesso alone will not stop SID; a sizing must be applied before using a gesso.
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The viscosity of acrylic can be successfully reduced by using suitable extenders that maintain the integrity of the paint film. There are retarders to slow drying and extend "workability" time, and "flow releases" to increase color-blending ability.
Properties.
Grades.
Commercial acrylic paints come in two grades by manufacturers:
Differences between acrylic and oil paint.
The vehicle and binder of oil paints is linseed oil (or another drying oil), whereas acrylic paint has water as the vehicle for an emulsion (suspension) of acrylic polymer, which serves as the binder. Thus, oil paint is said to be "oil-based", whereas acrylic paint is "water-based" (or sometimes "water-borne").
The main practical difference between most acrylics and oil paints is the inherent drying time. Oils allow for more time to blend colors and apply even glazes over underpaintings. This slow-drying aspect of oil can be seen as an advantage for certain techniques, but it impedes an artist trying to work quickly. The fast evaporation of water from regular acrylic paint films can be slowed with the use of acrylic retarders. Retarders are generally glycol or glycerin-based additives. The addition of a retarder slows the evaporation rate of the water.
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Oil paints may require the use of solvents such as mineral spirits or turpentine to thin the paint and clean up. These solvents generally have some level of toxicity and can be found objectionable. Relatively recently, water-miscible oil paints have been developed for artists' use. Oil paint films can gradually yellow and lose their flexibility over time creating cracks in the paint film; the "fat over lean" rule must be observed to ensure its durability.
Oil paint has a higher pigment load than acrylic paint. As linseed oil contains a smaller molecule than acrylic paint, oil paint is able to absorb substantially more pigment. Oil provides a refractive index that is less clear than acrylic dispersions, which imparts a unique "look and feel" to the resultant paint film. Not all the pigments of oil paints are available in acrylics and vice versa, as each medium has different chemical sensitivities. Some historical pigments are alkali sensitive, and therefore cannot be made in an acrylic emulsion; others are just too difficult to formulate. Approximate "hue" color formulations, that do not contain the historical pigments, are typically offered as substitutes.
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Because of acrylic paint's more flexible nature and more consistent drying time between layers, an artist does not have to follow the same rules of oil painting, where more medium must be applied to each layer to avoid cracking. It usually takes 10–20 minutes for one to two layers of acrylic paint to dry, depending on the brand, quality, and humidity levels of the surrounding environment. Some professional grades of acrylic paint can take 20–30 minutes or even more than an hour. Although canvas needs to be properly primed before painting with oils to prevent the paint medium from eventually rotting the canvas, acrylic can be safely applied straight to the canvas. The rapid drying of acrylic paint tends to discourage blending of color and use of wet-in-wet technique as in oil painting. Even though acrylic retarders can slow drying time to several hours, it remains a relatively fast-drying medium and adding too much acrylic retarder can prevent the paint from ever drying properly.
Meanwhile, acrylic paint is very elastic, which prevents cracking from occurring. Acrylic paint's binder is acrylic polymer emulsion – as this binder dries, the paint remains flexible.
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Another difference between oil and acrylic paints is the versatility offered by acrylic paints. Acrylics are very useful in mixed media, allowing the use of pastel (oil and chalk), charcoal and pen (among others) on top of the dried acrylic painted surface. Mixing other bodies into the acrylic is possible—sand, rice, and even pasta may be incorporated in the artwork. Mixing artist or student grade acrylic paint with household acrylic emulsions is possible, allowing the use of premixed tints straight from the tube or tin, and thereby presenting the painter with a vast color range at their disposal. This versatility is also illustrated by the variety of additional artistic uses for acrylics. Specialized acrylics have been manufactured and used for linoblock printing, face painting, airbrushing, watercolor-like techniques, and fabric screen printing.
Another difference between oil and acrylic paint is the cleanup. Acrylic paint can be cleaned out of a brush with any soap, while oil paint needs a specific type to be sure to get all the oil out of the brushes. Also, it is easier to let a palette with oil paint dry and then scrape the paint off, whereas one can easily clean wet acrylic paint with water.
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Difference between acrylic and watercolor paint.
The biggest difference is that acrylic paint is opaque, whereas watercolor paint is translucent in nature. Watercolors take about 5 to 15 minutes to dry while acrylics take about 10 to 20 minutes. In order to change the tone or shade of a watercolor pigment, one changes the percentage of water mixed in to the color. For brighter colors, one adds more water. For darker colors, one adds less water. In order to create lighter or darker colors with acrylic paints, one adds white or black.
Another difference is that watercolors must be painted onto a porous surface, primarily watercolor paper. Acrylic paints can be used on many different surfaces.
Both acrylic and watercolor are easy to clean up with water. Acrylic paint should be cleaned with soap and water immediately following use. Watercolor paint can be cleaned with just water.
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Angular momentum
Angular momentum (sometimes called moment of momentum or rotational momentum) is the rotational analog of linear momentum. It is an important physical quantity because it is a conserved quantity – the total angular momentum of a closed system remains constant. Angular momentum has both a direction and a magnitude, and both are conserved. Bicycles and motorcycles, flying discs, rifled bullets, and gyroscopes owe their useful properties to conservation of angular momentum. Conservation of angular momentum is also why hurricanes form spirals and neutron stars have high rotational rates. In general, conservation limits the possible motion of a system, but it does not uniquely determine it.
The three-dimensional angular momentum for a point particle is classically represented as a pseudovector , the cross product of the particle's position vector (relative to some origin) and its momentum vector; the latter is in Newtonian mechanics. Unlike linear momentum, angular momentum depends on where this origin is chosen, since the particle's position is measured from it.
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