Split (1)

train · 367k rows

text stringlengths 9 2.4k
However, ongoing political violence, which the ANC attributed to a state-sponsored third force, led to recurrent tensions. Most dramatically, after the Boipatong massacre of June 1992, the ANC announced that it was withdrawing from negotiations indefinitely. It faced further casualties in the Bisho massacre, the Shell House massacre, and in other clashes with state forces and supporters of the Inkatha Freedom Party (IFP). However, once negotiations resumed, they resulted in November 1993 in an interim Constitution, which governed South Africa's first democratic elections on 27 April 1994. In the elections, the ANC won an overwhelming 62.65% majority of the vote. Mandela was elected president and formed a coalition Government of National Unity, which, under the provisions of the interim Constitution, also included the National Party and IFP. The ANC has controlled the national government since then. Breakaways. In the post-apartheid era, several significant breakaway groups have been formed by former ANC members. The first is the Congress of the People, founded by Mosiuoa Lekota in 2008 in the aftermath of the Polokwane elective conference, when the ANC declined to re-elect Thabo Mbeki as its president and instead compelled his resignation from the national presidency. The second breakaway is the Economic Freedom Fighters, founded in 2013 after youth leader Julius Malema was expelled from the ANC. Before these, the most important split in the ANC's history occurred in 1959, when Robert Sobukwe led a splinter faction of African nationalists to the new Pan Africanist Congress.
uMkhonto weSizwe rose to prominence in December 2023, when former president Jacob Zuma announced that, while planning to remain a lifelong member of the ANC, he would not be campaigning for the ANC in the 2024 South African general election, and would instead be voting for MK. In July 2024, Jacob Zuma was expelled from the ANC, because of campaigning for a rival party (MK party) in the 29 May general election. Current structure and composition. Leadership. Under the ANC constitution, every member of the ANC belongs to a local branch, and branch members select the organisation's policies and leaders. They do so primarily by electing delegates to the National Conference, which is currently convened every five years. Between conferences, the organisation is led by its 86-member National Executive Committee, which is elected at each conference. The most senior members of the National Executive Committee are the so-called Top Six officials, the ANC president primary among them. A symmetrical process occurs at the subnational levels: each of the nine provincial executive committees and regional executive committees are elected at provincial and regional elective conferences respectively, also attended by branch delegates; and branch officials are elected at branch general meetings.
Leagues. The ANC has three leagues: the Women's League, the Youth League and the Veterans' League. Under the ANC constitution, the leagues are autonomous bodies with the scope to devise their own constitutions and policies; for the purpose of national conferences, they are treated somewhat like provinces, with voting delegates and the power to nominate leadership candidates. Tripartite Alliance. The ANC is recognised as the leader of a three-way alliance, known as the Tripartite Alliance, with the SACP and Congress of South African Trade Unions (COSATU). The alliance was formalised in mid-1990, after the ANC was unbanned, but has deeper historical roots: the SACP had worked closely with the ANC in exile, and COSATU had aligned itself with the Freedom Charter and Congress Alliance in 1987. The membership and leadership of the three organisations has traditionally overlapped significantly. The alliance constitutes a "de facto" electoral coalition: the SACP and COSATU do not contest in government elections, but field candidates through the ANC, hold senior positions in the ANC, and influence party policy. However, the SACP, in particular, has frequently threatened to field its own candidates, and in 2017 it did so for the first time, running against the ANC in by-elections in the Metsimaholo municipality, Free State.
Electoral candidates. Under South Africa's closed-list proportional representation electoral system, parties have immense power in selecting candidates for legislative bodies. The ANC's internal candidate selection process is overseen by so-called "list committees" and tends to involve a degree of broad democratic participation, especially at the local level, where ANC branches vote to nominate candidates for the local government elections. Between 2003 and 2008, the ANC also gained a significant number of members through the controversial floor crossing process, which occurred especially at the local level. The leaders of the executive in each sphere of government – the president, the provincial premiers, and the mayors – are indirectly elected after each election. In practice, the selection of ANC candidates for these positions is highly centralised, with the ANC caucus voting together to elect a pre-decided candidate. Although the ANC does not always announce whom its caucuses intend to elect, the National Assembly has thus far always elected the ANC president as the national president.
Cadre deployment. The ANC has adhered to a formal policy of cadre deployment since 1985. In the post-apartheid era, the policy includes but is not exhausted by selection of candidates for elections and government positions: it also entails that the central organisation "deploys" ANC members to various other strategic positions in the party, state, and economy. Ideology and policies. The ANC prides itself on being a broad church, and, like many dominant parties, resembles a catch-all party, accommodating a range of ideological tendencies. As Mandela told "The Washington Post" in 1990: The ANC has never been a political party. It was formed as a parliament of the African people. Right from the start, up to now, the ANC is a coalition, if you want, of people of various political affiliations. Some will support free enterprise, others socialism. Some are conservatives, others are liberals. We are united solely by our determination to oppose racial oppression. That is the only thing that unites us. There is no question of ideology as far as the odyssey of the ANC is concerned, because any question approaching ideology would split the organization from top to bottom. Because we have no connection whatsoever except at this one, of our determination to dismantle apartheid.
The post-apartheid ANC continues to identify itself foremost as a liberation movement, pursuing "the complete liberation of the country from all forms of discrimination and national oppression". It also continues to claim the Freedom Charter of 1955 as "the basic policy document of the ANC". However, as NEC member Jeremy Cronin noted in 2007, the various broad principles of the Freedom Charter have been given different interpretations, and emphasised to differing extents, by different groups within the organisation. Nonetheless, some basic commonalities are visible in the policy and ideological preferences of the organisation's mainstream. Non-racialism. The ANC is committed to the ideal of non-racialism and to opposing "any form of racial, tribalistic or ethnic exclusivism or chauvinism". National Democratic Revolution.
Economic interventionism. Since 1994, consecutive ANC governments have held a strong preference for a significant degree of state intervention in the economy. The ANC's first comprehensive articulation of its post-apartheid economic policy framework was set out in the Reconstruction and Development Programme (RDP) document of 1994, which became its electoral manifesto and also, under the same name, the flagship policy of Nelson Mandela's government. The RDP aimed both to redress the socioeconomic inequalities created by colonialism and apartheid, and to promote economic growth and development; state intervention was judged a necessary step towards both goals. Specifically, the state was to intervene in the economy through three primary channels: a land reform programme; a degree of economic planning, through industrial and trade policy; and state investments in infrastructure and the provision of basic services, including health and education. Although the RDP was abandoned in 1996, these three channels of state economic intervention have remained mainstays of subsequent ANC policy frameworks.
Neoliberal turn. In 1996, Mandela's government replaced the RDP with the Growth Employment and Redistribution (GEAR) programme, which was maintained under President Thabo Mbeki, Mandela's successor. GEAR has been characterised as a neoliberal policy, and it was disowned by both COSATU and the SACP. While some analysts viewed Mbeki's economic policy as undertaking the uncomfortable macroeconomic adjustments necessary for long-term growth, others – notably Patrick Bond – viewed it as a reflection of the ANC's failure to implement genuinely radical transformation after 1994. Debate about ANC commitment to redistribution on a socialist scale has continued: in 2013, the country's largest trade union, the National Union of Metalworkers of South Africa, withdrew its support for the ANC on the basis that "the working class cannot any longer see the ANC or the SACP as its class allies in any meaningful sense". It is evident, however, that the ANC never embraced free-market capitalism, and continued to favour a mixed economy: even as the debate over GEAR raged, the ANC declared itself (in 2004) a social-democratic party, and it was at that time presiding over phenomenal expansions of its black economic empowerment programme and the system of social grants.
Developmental state. As its name suggests, the RDP emphasised state-led development – that is, a developmental state – which the ANC has typically been cautious, at least in its rhetoric, to distinguish from the neighbouring concept of a welfare state. In the mid-2000s, during Mbeki's second term, the notion of a developmental state was revived in South African political discourse when the national economy worsened; and the 2007 National Conference whole-heartedly endorsed developmentalism in its policy resolutions, calling for a state "at the centre of a mixed economy... which leads and guides that economy and which intervenes in the interest of the people as a whole". The proposed developmental state was also central to the ANC's campaign in the 2009 elections, and it remains a central pillar of the policy of the current government, which seeks to build a "capable and developmental" state. In this regard, ANC politicians often cite China as an aspirational example. A discussion document ahead of the ANC's 2015 National General Council proposed that:
China['s] economic development trajectory remains a leading example of the triumph of humanity over adversity. The exemplary role of the collective leadership of the Communist Party of China in this regard should be a guiding lodestar of our own struggle. Radical economic transformation. Towards the end of Jacob Zuma's presidency, an ANC faction aligned to Zuma pioneered a new policy platform referred to as radical economic transformation (RET). Zuma announced the new focus on RET during his February 2017 State of the Nation address, and later that year, explaining that it had been adopted as ANC policy and therefore as government policy, defined it as entailing "fundamental change in the structures, systems, institutions and patterns of ownership and control of the economy, in favour of all South Africans, especially the poor". Arguments for RET were closely associated with the rhetorical concept of white monopoly capital. At the 54th National Conference in 2017, the ANC endorsed a number of policy principles advocated by RET supporters, including their proposal to pursue land expropriation without compensation as a matter of national policy.
Foreign policy and relations. The ANC has long had close ties with China and the Chinese Communist Party (CCP), with the CCP having supported ANC's struggle of apartheid since 1961. In 2008, the two parties signed a memorandum of understanding to train ANC members in China. President Cyril Ramaphosa and the ANC have not condemned the Russian invasion of Ukraine, and have faced criticism from opposition parties, public commentators, academics, civil society organisations, and former ANC members due to this. The ANC youth wing has meanwhile condemned sanctions against Russia and denounced NATO's eastward expansion as "fascistic". Officials representing the ANC Youth League acted as international observers for Russia's staged referendum to annex Ukrainian territory conquered during the war. In February 2024 ANC Secretary-General Fikile Mbalula attend a "forum on combating Western neocolonialism" hosted by Russia, thereby drawing further criticism for the party's perceived support for Russia's invasion. The ANC had received large donations from the Putin linked Russian oligarch Viktor Vekselberg, whilst the party's investment arm, Chancellor House, has a joint investment with Vekselberg in a South African manganese mine.
Symbols and media. Flag and logo. The logo of the ANC incorporates a spear and shield – symbolising the historical and ongoing struggle, armed and otherwise, against colonialism and racial oppression – and a wheel, which is borrowed from the 1955 Congress of the People campaign and therefore symbolises a united and non-racial movement for freedom and equality. The logo uses the same colours as the ANC flag, which comprises three horizontal stripes of equal width in black, green and gold. The black symbolises the native people of South Africa; the green represents the land of South Africa; and the gold represents the country's mineral and other natural wealth. The black, green and gold tricolour also appeared on the flag of the KwaZulu bantustan and appears on the flag of the ANC's rival, the IFP; and all three colours appear in the post-apartheid South African national flag. Publications. Since 1996, the ANC Department of Political Education has published the quarterly "Umrabulo" political discussion journal; and "ANC Today", a weekly online newsletter, was launched in 2001 to offset the alleged bias of the press. In addition, since 1972, it has been traditional for the ANC president to publish annually a so-called January 8 Statement: a reflective letter sent to members on 8 January, the anniversary of the organisation's founding. In earlier years, the ANC published a range of periodicals, the most important of which was the monthly journal "Sechaba" (1967–1990), printed in the German Democratic Republic and banned by the apartheid government. The ANC's Radio Freedom also gained a wide audience during apartheid.
Amandla. "Amandla ngawethu", or the Sotho variant "Matla ke arona", is a common rallying call at ANC meetings, roughly meaning "power to the people". It is also common for meetings to sing so-called struggle songs, which were sung during anti-apartheid meetings and in MK camps. In the case of at least two of these songs – "Dubula ibhunu" and "Umshini wami" – this has caused controversy in recent years. Criticism and controversy. The ANC has received criticism from both internal and external sources. Internally Mandela publicly criticized the party, following the conclusion of his presidency, for ignoring instances of corruption and mismanagement, whilst allowing for the growth of a culture of racial and ideological intolerance. Corruption controversies. The most prominent corruption case involving the ANC relates to a series of bribes paid to companies involved in the ongoing R55 billion Arms Deal saga, which resulted in a long term jail sentence to then Deputy President Jacob Zuma's legal adviser Schabir Shaik. Zuma, the former South African President, was charged with fraud, bribery and corruption in the Arms Deal, but the charges were subsequently withdrawn by the National Prosecuting Authority of South Africa due to their delay in prosecution. The ANC has also been criticised for its subsequent abolition of the Scorpions, the multidisciplinary agency that investigated and prosecuted organised crime and corruption, and was heavily involved in the investigation into Zuma and Shaik. Tony Yengeni, in his position as chief whip of the ANC and head of the Parliaments defence committee has recently been named as being involved in bribing the German company ThyssenKrupp over the purchase of four corvettes for the SANDF.
Other corruption issues in the 2000s included the sexual misconduct and criminal charges of Beaufort West municipal manager Truman Prince, and the Oilgate scandal, in which millions of Rand in funds from a state-owned company were funnelled into ANC coffers. The ANC has also been accused of using government and civil society to fight its political battles against opposition parties such as the Democratic Alliance. The result has been a number of complaints and allegations that none of the political parties truly represent the interests of the poor. This has resulted in the "No Land! No House! No Vote!" Campaign which became very prominent during elections. In 2018, "The New York Times" reported on the killings of ANC corruption whistleblowers. During an address on 28 October 2021, former president Thabo Mbeki commented on the history of corruption within the ANC. He reflected that Mandela had already warned in 1997 that the ANC was attracting individuals who viewed the party as "a route to power and self-enrichment." He added that the ANC leadership "did not know how to deal with this problem." During a lecture on 10 December, Mbeki reiterated concerns about "careerists" within the party, and stressed the need to "purge itself of such members".
In May 2024, the International Consortium of Investigative Journalists in association with amaBhungane showed in documents that R200 million in the ANC's election fund was siphoned off to the church of controversial archbishop Bheki Lukhele in Eswatini; the Chief Financial Officer of the ANC, Bongani Mahlalela along with the Ambassador of Eswatini to Belgium, Sibusisiwe Mngomezulu, were implicated in the scheme. Condemnation over Secrecy Bill. In late 2011, the ANC was heavily criticised over the passage of the Protection of State Information Bill, which opponents claimed would improperly restrict the freedom of the press. Opposition to the bill included otherwise ANC-aligned groups such as COSATU. Notably, Nelson Mandela and other Nobel laureates Nadine Gordimer, Archbishop Desmond Tutu, and F. W. de Klerk have expressed disappointment with the bill for not meeting standards of constitutionality and aspirations for freedom of information and expression. Role in the Marikana killings. The ANC have been criticised for its role in failing to prevent 16 August 2012 massacre of Lonmin miners at Marikana in the Northwest. Some allege that Police Commissioner Riah Phiyega and Police Minister Nathi Mthethwa gave the go ahead for the police action against the miners on that day.
Commissioner Phiyega of the ANC came under further criticism as being insensitive and uncaring when she was caught smiling and laughing during the Farlam Commission's video playback of the massacre. In 2014, Archbishop Desmond Tutu announced that he could no longer bring himself to vote for the ANC, as it was no longer the party that he and Nelson Mandela fought for. He stated that the party had lost its way, and was in danger of becoming a corrupt entity in power. Financial mismanagement. Since at least 2017, the ANC has encountered significant problems related to financial mismanagement. According to a report filed by the former treasurer-general Zweli Mkhize in December 2017, the ANC was technically insolvent as its liabilities exceeded its assets. These problems continued into the second half of 2021. By September 2021, the ANC had reportedly amassed a debt exceeding R200-million, including over R100-million owed to the South African Revenue Service. Beginning in May 2021, the ANC failed to pay monthly staff salaries on time. Having gone without pay for three consecutive months, workers planned a strike in late August 2021. In response, the ANC initiated a crowdfunding campaign to raise money for staff salaries. By November 2021, its Cape Town staff was approaching their fourth month without salaries, while medical aid and provident fund contributions had been suspended in various provinces. The party has countered that the Political Party Funding Act, which prohibits anonymous contributions, has dissuaded some donors who previously injected money for salaries.
State capture. In January 2018, then-President Jacob Zuma established the Zondo Commission to investigate allegations of state capture, corruption, and fraud in the public sector. Over the following four years, the Commission heard testimony from over 250 witnesses and collected more than 150,000 pages of evidence. After several extensions, the first part of the final three-part report was published on 4 January 2022. The report found that the ANC, including Zuma and his political allies, had benefited from the extensive corruption of state enterprises, including the South African Revenue Service. It also found that the ANC "simply did not care that state entities were in decline during state capture or they slept on the job – or they simply didn't know what to do."
Amphetamine Amphetamine (contracted from alpha-methylphenethylamine) is a central nervous system (CNS) stimulant that is used in the treatment of attention deficit hyperactivity disorder (ADHD), narcolepsy, and obesity; it is also used to treat binge eating disorder in the form of its inactive prodrug lisdexamfetamine. Amphetamine was discovered as a chemical in 1887 by Lazăr Edeleanu, and then as a drug in the late 1920s. It exists as two enantiomers: levoamphetamine and dextroamphetamine. "Amphetamine" properly refers to a specific chemical, the racemic free base, which is equal parts of the two enantiomers in their pure amine forms. The term is frequently used informally to refer to any combination of the enantiomers, or to either of them alone. Historically, it has been used to treat nasal congestion and depression. Amphetamine is also used as an athletic performance enhancer and cognitive enhancer, and recreationally as an aphrodisiac and euphoriant. It is a prescription drug in many countries, and unauthorized possession and distribution of amphetamine are often tightly controlled due to the significant health risks associated with recreational use.
The first amphetamine pharmaceutical was Benzedrine, a brand which was used to treat a variety of conditions. Pharmaceutical amphetamine is prescribed as racemic amphetamine, Adderall, dextroamphetamine, or the inactive prodrug lisdexamfetamine. Amphetamine increases monoamine and excitatory neurotransmission in the brain, with its most pronounced effects targeting the norepinephrine and dopamine neurotransmitter systems. At therapeutic doses, amphetamine causes emotional and cognitive effects such as euphoria, change in desire for sex, increased wakefulness, and improved cognitive control. It induces physical effects such as improved reaction time, fatigue resistance, decreased appetite, elevated heart rate, and increased muscle strength. Larger doses of amphetamine may impair cognitive function and induce rapid muscle breakdown. Addiction is a serious risk with heavy recreational amphetamine use, but is unlikely to occur from long-term medical use at therapeutic doses. Very high doses can result in psychosis (e.g., hallucinations, delusions and paranoia) which rarely occurs at therapeutic doses even during long-term use. Recreational doses are generally much larger than prescribed therapeutic doses and carry a far greater risk of serious side effects.
Amphetamine belongs to the phenethylamine class. It is also the parent compound of its own structural class, the substituted amphetamines, which includes prominent substances such as bupropion, cathinone, MDMA, and methamphetamine. As a member of the phenethylamine class, amphetamine is also chemically related to the naturally occurring trace amine neuromodulators, specifically phenethylamine and , both of which are produced within the human body. Phenethylamine is the parent compound of amphetamine, while is a positional isomer of amphetamine that differs only in the placement of the methyl group. Uses. Medical. ADHD. Long-term amphetamine exposure at sufficiently high doses in some animal species is known to produce abnormal dopamine system development or nerve damage, but, in humans with ADHD, long-term use of pharmaceutical amphetamines at therapeutic doses appears to improve brain development and nerve growth. Reviews of magnetic resonance imaging (MRI) studies suggest that long-term treatment with amphetamine decreases abnormalities in brain structure and function found in subjects with ADHD, and improves function in several parts of the brain, such as the right caudate nucleus of the basal ganglia.
Reviews of clinical stimulant research have established the safety and effectiveness of long-term continuous amphetamine use for the treatment of ADHD. Randomized controlled trials of continuous stimulant therapy for the treatment of ADHD spanning 2 years have demonstrated treatment effectiveness and safety. Two reviews have indicated that long-term continuous stimulant therapy for ADHD is effective for reducing the core symptoms of ADHD (i.e., hyperactivity, inattention, and impulsivity), enhancing quality of life and academic achievement, and producing improvements in a large number of functional outcomes across 9 categories of outcomes related to academics, antisocial behavior, driving, non-medicinal drug use, obesity, occupation, self-esteem, service use (i.e., academic, occupational, health, financial, and legal services), and social function. Additionally, a 2024 meta-analytic systematic review reported moderate improvements in quality of life when amphetamine treatment is used for ADHD. One review highlighted a nine-month randomized controlled trial of amphetamine treatment for ADHD in children that found an average increase of 4.5 IQ points, continued increases in attention, and continued decreases in disruptive behaviors and hyperactivity. Another review indicated that, based upon the longest follow-up studies conducted to date, lifetime stimulant therapy that begins during childhood is continuously effective for controlling ADHD symptoms and reduces the risk of developing a substance use disorder as an adult. A 2025 meta-analytic systematic review of 113 randomized controlled trials demonstrated that stimulant medications significantly improved core ADHD symptoms in adults over a three-month period, with good acceptability compared to other pharmacological and non-pharmacological treatments.
Models of ADHD suggest that it is associated with functional impairments in some of the brain's neurotransmitter systems; these functional impairments involve impaired dopamine neurotransmission in the mesocorticolimbic projection and norepinephrine neurotransmission in the noradrenergic projections from the locus coeruleus to the prefrontal cortex. Stimulants like methylphenidate and amphetamine are effective in treating ADHD because they increase neurotransmitter activity in these systems. Approximately 80% of those who use these stimulants see improvements in ADHD symptoms. Children with ADHD who use stimulant medications generally have better relationships with peers and family members, perform better in school, are less distractible and impulsive, and have longer attention spans. The Cochrane reviews on the treatment of ADHD in children, adolescents, and adults with pharmaceutical amphetamines stated that short-term studies have demonstrated that these drugs decrease the severity of symptoms, but they have higher discontinuation rates than non-stimulant medications due to their adverse side effects. A Cochrane review on the treatment of ADHD in children with tic disorders such as Tourette syndrome indicated that stimulants in general do not make tics worse, but high doses of dextroamphetamine could exacerbate tics in some individuals.
Binge eating disorder. Binge eating disorder (BED) is characterized by recurrent and persistent episodes of compulsive binge eating. These episodes are often accompanied by marked distress and a feeling of loss of control over eating. The pathophysiology of BED is not fully understood, but it is believed to involve dysfunctional dopaminergic reward circuitry along the cortico-striatal-thalamic-cortical loop. As of July 2024, lisdexamfetamine is the only USFDA- and TGA-approved pharmacotherapy for BED. Evidence suggests that lisdexamfetamine's treatment efficacy in BED is underpinned at least in part by a psychopathological overlap between BED and ADHD, with the latter conceptualized as a cognitive control disorder that also benefits from treatment with lisdexamfetamine.
Medical reviews of randomized controlled trials have demonstrated that lisdexamfetamine, at doses between 50–70 mg, is safe and effective for the treatment of moderate-to-severe BED in adults. These reviews suggest that lisdexamfetamine is persistently effective at treating BED and is associated with significant reductions in the number of binge eating days and binge eating episodes per week. Furthermore, a meta-analytic systematic review highlighted an open-label, 12-month extension safety and tolerability study that reported lisdexamfetamine remained effective at reducing the number of binge eating days for the duration of the study. In addition, both a review and a meta-analytic systematic review found lisdexamfetamine to be superior to placebo in several secondary outcome measures, including persistent binge eating cessation, reduction of obsessive-compulsive related binge eating symptoms, reduction of body-weight, and reduction of triglycerides. Lisdexamfetamine, like all pharmaceutical amphetamines, has direct appetite suppressant effects that may be therapeutically useful in both BED and its comorbidities. Based on reviews of neuroimaging studies involving BED-diagnosed participants, therapeautic neuroplasticity in dopaminergic and noradrenergic pathways from long-term use of lisdexamfetamine may be implicated in lasting improvements in the regulation of eating behaviors that are observed.
Narcolepsy. Narcolepsy is a chronic sleep-wake disorder that is associated with excessive daytime sleepiness, cataplexy, and sleep paralysis. Patients with narcolepsy are diagnosed as either type 1 or type 2, with only the former presenting cataplexy symptoms. Type 1 narcolepsy results from the loss of approximately 70,000 orexin-releasing neurons in the lateral hypothalamus, leading to significantly reduced cerebrospinal orexin levels; this reduction is a diagnostic biomarker for type 1 narcolepsy. Lateral hypothalamic orexin neurons innervate every component of the ascending reticular activating system (ARAS), which includes noradrenergic, dopaminergic, histaminergic, and serotonergic nuclei that promote wakefulness. Amphetamine’s therapeutic mode of action in narcolepsy primarily involves increasing monoamine neurotransmitter activity in the ARAS. This includes noradrenergic neurons in the locus coeruleus, dopaminergic neurons in the ventral tegmental area, histaminergic neurons in the tuberomammillary nucleus, and serotonergic neurons in the dorsal raphe nucleus. Dextroamphetamine, the more dopaminergic enantiomer of amphetamine, is particularly effective at promoting wakefulness because dopamine release has the greatest influence on cortical activation and cognitive arousal, relative to other monoamines. In contrast, levoamphetamine may have a greater effect on cataplexy, a symptom more sensitive to the effects of norepinephrine and serotonin. Noradrenergic and serotonergic nuclei in the ARAS are involved in the regulation of the REM sleep cycle and function as "REM-off" cells, with amphetamine's effect on norepinephrine and serotonin contributing to the suppression of REM sleep and a possible reduction of cataplexy at high doses.
The American Academy of Sleep Medicine (AASM) 2021 clinical practice guideline conditionally recommends dextroamphetamine for the treatment of both type 1 and type 2 narcolepsy. Treatment with pharmaceutical amphetamines is generally less preferred relative to other stimulants (e.g., modafinil) and is considered a third-line treatment option. Medical reviews indicate that amphetamine is safe and effective for the treatment of narcolepsy. Amphetamine appears to be most effective at improving symptoms associated with hypersomnolence, with three reviews finding clinically significant reductions in daytime sleepiness in patients with narcolepsy. Additionally, these reviews suggest that amphetamine may dose-dependently improve cataplexy symptoms. However, the quality of evidence for these findings is low and is consequently reflected in the AASM's conditional recommendation for dextroamphetamine as a treatment option for narcolepsy. Enhancing performance. Cognitive performance.
Physical performance. Amphetamine is used by some athletes for its psychological and athletic performance-enhancing effects, such as increased endurance and alertness; however, non-medical amphetamine use is prohibited at sporting events that are regulated by collegiate, national, and international anti-doping agencies. In healthy people at oral therapeutic doses, amphetamine has been shown to increase muscle strength, acceleration, athletic performance in anaerobic conditions, and endurance (i.e., it delays the onset of fatigue), while improving reaction time. Amphetamine improves endurance and reaction time primarily through reuptake inhibition and release of dopamine in the central nervous system. Amphetamine and other dopaminergic drugs also increase power output at fixed levels of perceived exertion by overriding a "safety switch", allowing the core temperature limit to increase in order to access a reserve capacity that is normally off-limits. At therapeutic doses, the adverse effects of amphetamine do not impede athletic performance; however, at much higher doses, amphetamine can induce effects that severely impair performance, such as rapid muscle breakdown and elevated body temperature.
Recreational. Amphetamine, specifically the more dopaminergic dextrorotatory enantiomer (dextroamphetamine), is also used recreationally as a euphoriant and aphrodisiac, and like other amphetamines; is used as a club drug for its energetic and euphoric high. Dextroamphetamine (d-amphetamine) is considered to have a high potential for misuse in a recreational manner since individuals typically report feeling euphoric, more alert, and more energetic after taking the drug. A notable part of the 1960s mod subculture in the UK was recreational amphetamine use, which was used to fuel all-night dances at clubs like Manchester's Twisted Wheel. Newspaper reports described dancers emerging from clubs at 5 a.m. with dilated pupils. Mods used the drug for stimulation and alertness, which they viewed as different from the intoxication caused by alcohol and other drugs. Dr.
Mods used the drug for stimulation and alertness, which they viewed as different from the intoxication caused by alcohol and other drugs. Dr. Large recreational doses of dextroamphetamine may produce symptoms of dextroamphetamine overdose. Recreational users sometimes open dexedrine capsules and crush the contents in order to insufflate (snort) it or subsequently dissolve it in water and inject it. Immediate-release formulations have higher potential for abuse via insufflation (snorting) or intravenous injection due to a more favorable pharmacokinetic profile and easy crushability (especially tablets). Injection into the bloodstream can be dangerous because insoluble fillers within the tablets can block small blood vessels. Chronic overuse of dextroamphetamine can lead to severe drug dependence, resulting in withdrawal symptoms when drug use stops.
Contraindications. According to the International Programme on Chemical Safety (IPCS) and the U.S. Food and Drug Administration (FDA), amphetamine is contraindicated in people with a history of drug abuse, cardiovascular disease, severe agitation, or severe anxiety. It is also contraindicated in individuals with advanced arteriosclerosis (hardening of the arteries), glaucoma (increased eye pressure), hyperthyroidism (excessive production of thyroid hormone), or moderate to severe hypertension. These agencies indicate that people who have experienced allergic reactions to other stimulants or who are taking monoamine oxidase inhibitors (MAOIs) should not take amphetamine, although safe concurrent use of amphetamine and monoamine oxidase inhibitors has been documented. These agencies also state that anyone with anorexia nervosa, bipolar disorder, depression, hypertension, liver or kidney problems, mania, psychosis, Raynaud's phenomenon, seizures, thyroid problems, tics, or Tourette syndrome should monitor their symptoms while taking amphetamine. Evidence from human studies indicates that therapeutic amphetamine use does not cause developmental abnormalities in the fetus or newborns (i.e., it is not a human teratogen), but amphetamine abuse does pose risks to the fetus. Amphetamine has also been shown to pass into breast milk, so the IPCS and the FDA advise mothers to avoid breastfeeding when using it. Due to the potential for reversible growth impairments, the FDA advises monitoring the height and weight of children and adolescents prescribed an amphetamine pharmaceutical.
Adverse effects. Physical. Cardiovascular side effects can include hypertension or hypotension from a vasovagal response, Raynaud's phenomenon (reduced blood flow to the hands and feet), and tachycardia (increased heart rate). Sexual side effects in males may include erectile dysfunction, frequent erections, or prolonged erections. Gastrointestinal side effects may include abdominal pain, constipation, diarrhea, and nausea. Other potential physical side effects include appetite loss, blurred vision, dry mouth, excessive grinding of the teeth, nosebleed, profuse sweating, rhinitis medicamentosa (drug-induced nasal congestion), reduced seizure threshold, tics (a type of movement disorder), and weight loss. Dangerous physical side effects are rare at typical pharmaceutical doses. Amphetamine stimulates the medullary respiratory centers, producing faster and deeper breaths. In a normal person at therapeutic doses, this effect is usually not noticeable, but when respiration is already compromised, it may be evident. Amphetamine also induces contraction in the urinary bladder sphincter, the muscle which controls urination, which can result in difficulty urinating. This effect can be useful in treating bed wetting and loss of bladder control. The effects of amphetamine on the gastrointestinal tract are unpredictable. If intestinal activity is high, amphetamine may reduce gastrointestinal motility (the rate at which content moves through the digestive system); however, amphetamine may increase motility when the smooth muscle of the tract is relaxed. Amphetamine also has a slight analgesic effect and can enhance the pain relieving effects of opioids.
FDA-commissioned studies from 2011 indicate that in children, young adults, and adults there is no association between serious adverse cardiovascular events (sudden death, heart attack, and stroke) and the medical use of amphetamine or other ADHD stimulants. However, amphetamine pharmaceuticals are contraindicated in individuals with cardiovascular disease. Psychological. At normal therapeutic doses, the most common psychological side effects of amphetamine include increased alertness, apprehension, concentration, initiative, self-confidence and sociability, mood swings (elated mood followed by mildly depressed mood), insomnia or wakefulness, and decreased sense of fatigue. Less common side effects include anxiety, change in libido, grandiosity, irritability, repetitive or obsessive behaviors, and restlessness; these effects depend on the user's personality and current mental state. Amphetamine psychosis (e.g., delusions and paranoia) can occur in heavy users. Although very rare, this psychosis can also occur at therapeutic doses during long-term therapy. According to the FDA, "there is no systematic evidence" that stimulants produce aggressive behavior or hostility.
Amphetamine has also been shown to produce a conditioned place preference in humans taking therapeutic doses, meaning that individuals acquire a preference for spending time in places where they have previously used amphetamine. Reinforcement disorders. Addiction. Addiction is a serious risk with heavy recreational amphetamine use, but is unlikely to occur from long-term medical use at therapeutic doses; in fact, lifetime stimulant therapy for ADHD that begins during childhood reduces the risk of developing substance use disorders as an adult. Pathological overactivation of the mesolimbic pathway, a dopamine pathway that connects the ventral tegmental area to the nucleus accumbens, plays a central role in amphetamine addiction. Individuals who frequently self-administer high doses of amphetamine have a high risk of developing an amphetamine addiction, since chronic use at high doses gradually increases the level of accumbal ΔFosB, a "molecular switch" and "master control protein" for addiction. Once nucleus accumbens ΔFosB is sufficiently overexpressed, it begins to increase the severity of addictive behavior (i.e., compulsive drug-seeking) with further increases in its expression. While there are currently no effective drugs for treating amphetamine addiction, regularly engaging in sustained aerobic exercise appears to reduce the risk of developing such an addiction. Exercise therapy improves clinical treatment outcomes and may be used as an adjunct therapy with behavioral therapies for addiction.
Biomolecular mechanisms. Chronic use of amphetamine at excessive doses causes alterations in gene expression in the mesocorticolimbic projection, which arise through transcriptional and epigenetic mechanisms. The most important transcription factors that produce these alterations are "Delta FBJ murine osteosarcoma viral oncogene homolog B" (ΔFosB), "cAMP response element binding protein" (CREB), and "nuclear factor-kappa B" (NF-κB). ΔFosB is the most significant biomolecular mechanism in addiction because ΔFosB overexpression (i.e., an abnormally high level of gene expression which produces a pronounced gene-related phenotype) in the D1-type medium spiny neurons in the nucleus accumbens is necessary and sufficient for many of the neural adaptations and regulates multiple behavioral effects (e.g., reward sensitization and escalating drug self-administration) involved in addiction. Once ΔFosB is sufficiently overexpressed, it induces an addictive state that becomes increasingly more severe with further increases in ΔFosB expression. It has been implicated in addictions to alcohol, cannabinoids, cocaine, methylphenidate, nicotine, opioids, phencyclidine, propofol, and substituted amphetamines, among others.
ΔJunD, a transcription factor, and G9a, a histone methyltransferase enzyme, both oppose the function of ΔFosB and inhibit increases in its expression. Sufficiently overexpressing ΔJunD in the nucleus accumbens with viral vectors can completely block many of the neural and behavioral alterations seen in chronic drug abuse (i.e., the alterations mediated by ΔFosB). Similarly, accumbal G9a hyperexpression results in markedly increased histone 3 lysine residue 9 dimethylation (H3K9me2) and blocks the induction of ΔFosB-mediated neural and behavioral plasticity by chronic drug use, which occurs via H3K9me2-mediated repression of transcription factors for ΔFosB and H3K9me2-mediated repression of various ΔFosB transcriptional targets (e.g., CDK5). ΔFosB also plays an important role in regulating behavioral responses to natural rewards, such as palatable food, sex, and exercise. Since both natural rewards and addictive drugs induce the expression of ΔFosB (i.e., they cause the brain to produce more of it), chronic acquisition of these rewards can result in a similar pathological state of addiction. Consequently, ΔFosB is the most significant factor involved in both amphetamine addiction and amphetamine-induced sexual addictions, which are compulsive sexual behaviors that result from excessive sexual activity and amphetamine use. These sexual addictions are associated with a dopamine dysregulation syndrome which occurs in some patients taking dopaminergic drugs.
The effects of amphetamine on gene regulation are both dose- and route-dependent. Most of the research on gene regulation and addiction is based upon animal studies with intravenous amphetamine administration at very high doses. The few studies that have used equivalent (weight-adjusted) human therapeutic doses and oral administration show that these changes, if they occur, are relatively minor. This suggests that medical use of amphetamine does not significantly affect gene regulation. Pharmacological treatments. there is no effective pharmacotherapy for amphetamine addiction. Reviews from 2015 and 2016 indicated that TAAR1-selective agonists have significant therapeutic potential as a treatment for psychostimulant addictions; however, the only compounds which are known to function as TAAR1-selective agonists are experimental drugs. Amphetamine addiction is largely mediated through increased activation of dopamine receptors and NMDA receptors in the nucleus accumbens; magnesium ions inhibit NMDA receptors by blocking the receptor calcium channel. One review suggested that, based upon animal testing, pathological (addiction-inducing) psychostimulant use significantly reduces the level of intracellular magnesium throughout the brain. Supplemental magnesium treatment has been shown to reduce amphetamine self-administration (i.e., doses given to oneself) in humans, but it is not an effective monotherapy for amphetamine addiction.
A systematic review and meta-analysis from 2019 assessed the efficacy of 17 different pharmacotherapies used in randomized controlled trials (RCTs) for amphetamine and methamphetamine addiction; it found only low-strength evidence that methylphenidate might reduce amphetamine or methamphetamine self-administration. There was low- to moderate-strength evidence of no benefit for most of the other medications used in RCTs, which included antidepressants (bupropion, mirtazapine, sertraline), antipsychotics (aripiprazole), anticonvulsants (topiramate, baclofen, gabapentin), naltrexone, varenicline, citicoline, ondansetron, prometa, riluzole, atomoxetine, dextroamphetamine, and modafinil. Behavioral treatments. A 2018 systematic review and network meta-analysis of 50 trials involving 12 different psychosocial interventions for amphetamine, methamphetamine, or cocaine addiction found that combination therapy with both contingency management and community reinforcement approach had the highest efficacy (i.e., abstinence rate) and acceptability (i.e., lowest dropout rate). Other treatment modalities examined in the analysis included monotherapy with contingency management or community reinforcement approach, cognitive behavioral therapy, 12-step programs, non-contingent reward-based therapies, psychodynamic therapy, and other combination therapies involving these.
Additionally, research on the neurobiological effects of physical exercise suggests that daily aerobic exercise, especially endurance exercise (e.g., marathon running), prevents the development of drug addiction and is an effective adjunct therapy (i.e., a supplemental treatment) for amphetamine addiction. Exercise leads to better treatment outcomes when used as an adjunct treatment, particularly for psychostimulant addictions. In particular, aerobic exercise decreases psychostimulant self-administration, reduces the reinstatement (i.e., relapse) of drug-seeking, and induces increased dopamine receptor D2 (DRD2) density in the striatum. This is the opposite of pathological stimulant use, which induces decreased striatal DRD2 density. One review noted that exercise may also prevent the development of a drug addiction by altering ΔFosB or immunoreactivity in the striatum or other parts of the reward system. Dependence and withdrawal. Drug tolerance develops rapidly in amphetamine abuse (i.e., recreational amphetamine use), so periods of extended abuse require increasingly larger doses of the drug in order to achieve the same effect.
According to a Cochrane review on withdrawal in individuals who compulsively use amphetamine and methamphetamine, "when chronic heavy users abruptly discontinue amphetamine use, many report a time-limited withdrawal syndrome that occurs within 24 hours of their last dose." This review noted that withdrawal symptoms in chronic, high-dose users are frequent, occurring in roughly 88% of cases, and persist for weeks with a marked "crash" phase occurring during the first week. Amphetamine withdrawal symptoms can include anxiety, drug craving, depressed mood, fatigue, increased appetite, increased movement or decreased movement, lack of motivation, sleeplessness or sleepiness, and lucid dreams. The review indicated that the severity of withdrawal symptoms is positively correlated with the age of the individual and the extent of their dependence. Mild withdrawal symptoms from the discontinuation of amphetamine treatment at therapeutic doses can be avoided by tapering the dose. Overdose. An amphetamine overdose can lead to many different symptoms, but is rarely fatal with appropriate care. The severity of overdose symptoms increases with dosage and decreases with drug tolerance to amphetamine. Tolerant individuals have been known to take as much as 5 grams of amphetamine in a day, which is roughly 100 times the maximum daily therapeutic dose. Symptoms of a moderate and extremely large overdose are listed below; fatal amphetamine poisoning usually also involves convulsions and coma. In 2013, overdose on amphetamine, methamphetamine, and other compounds implicated in an "amphetamine use disorder" resulted in an estimated 3,788 deaths worldwide ( deaths, 95% confidence).
Toxicity. In rodents and primates, sufficiently high doses of amphetamine cause dopaminergic neurotoxicity, or damage to dopamine neurons, which is characterized by dopamine terminal degeneration and reduced transporter and receptor function. There is no evidence that amphetamine is directly neurotoxic in humans. However, large doses of amphetamine may indirectly cause dopaminergic neurotoxicity as a result of hyperpyrexia, the excessive formation of reactive oxygen species, and increased autoxidation of dopamine. Animal models of neurotoxicity from high-dose amphetamine exposure indicate that the occurrence of hyperpyrexia (i.e., core body temperature ≥ 40 °C) is necessary for the development of amphetamine-induced neurotoxicity. Prolonged elevations of brain temperature above 40 °C likely promote the development of amphetamine-induced neurotoxicity in laboratory animals by facilitating the production of reactive oxygen species, disrupting cellular protein function, and transiently increasing blood–brain barrier permeability.
Psychosis. An amphetamine overdose can result in a stimulant psychosis that may involve a variety of symptoms, such as delusions and paranoia. A Cochrane review on treatment for amphetamine, dextroamphetamine, and methamphetamine psychosis states that about of users fail to recover completely. According to the same review, there is at least one trial that shows antipsychotic medications effectively resolve the symptoms of acute amphetamine psychosis. Psychosis rarely arises from therapeutic use. Drug interactions. Many types of substances are known to interact with amphetamine, resulting in altered drug action or metabolism of amphetamine, the interacting substance, or both. Inhibitors of enzymes that metabolize amphetamine (e.g., CYP2D6 and FMO3) will prolong its elimination half-life, meaning that its effects will last longer. Amphetamine also interacts with , particularly monoamine oxidase A inhibitors, since both MAOIs and amphetamine increase plasma catecholamines (i.e., norepinephrine and dopamine); therefore, concurrent use of both is dangerous. Amphetamine modulates the activity of most psychoactive drugs. In particular, amphetamine may decrease the effects of sedatives and depressants and increase the effects of stimulants and antidepressants. Amphetamine may also decrease the effects of antihypertensives and antipsychotics due to its effects on blood pressure and dopamine respectively. Zinc supplementation may reduce the minimum effective dose of amphetamine when it is used for the treatment of ADHD. Norepinephrine reuptake inhibitors (NRIs) like atomoxetine prevent norepinephrine release induced by amphetamines and have been found to reduce the stimulant, euphoriant, and sympathomimetic effects of dextroamphetamine in humans.
In general, there is no significant interaction when consuming amphetamine with food, but the pH of gastrointestinal content and urine affects the absorption and excretion of amphetamine, respectively. Acidic substances reduce the absorption of amphetamine and increase urinary excretion, and alkaline substances do the opposite. Due to the effect pH has on absorption, amphetamine also interacts with gastric acid reducers such as proton pump inhibitors and H2 antihistamines, which increase gastrointestinal pH (i.e., make it less acidic). Pharmacology. Pharmacodynamics. Amphetamine exerts its behavioral effects by altering the use of monoamines as neuronal signals in the brain, primarily in catecholamine neurons in the reward and executive function pathways of the brain. The concentrations of the main neurotransmitters involved in reward circuitry and executive functioning, dopamine and norepinephrine, increase dramatically in a dose-dependent manner by amphetamine because of its effects on monoamine transporters. The reinforcing and motivational salience-promoting effects of amphetamine are due mostly to enhanced dopaminergic activity in the mesolimbic pathway. The euphoric and locomotor-stimulating effects of amphetamine are dependent upon the magnitude and speed by which it increases synaptic dopamine and norepinephrine concentrations in the striatum.
Amphetamine has been identified as a potent full agonist of trace amine-associated receptor 1 (TAAR1), a and G protein-coupled receptor (GPCR) discovered in 2001, which is important for regulation of brain monoamines. Activation of increases production via adenylyl cyclase activation and inhibits monoamine transporter function. Monoamine autoreceptors (e.g., D2 short, presynaptic α2, and presynaptic 5-HT1A) have the opposite effect of TAAR1, and together these receptors provide a regulatory system for monoamines. Notably, amphetamine and trace amines possess high binding affinities for TAAR1, but not for monoamine autoreceptors. Imaging studies indicate that monoamine reuptake inhibition by amphetamine and trace amines is site specific and depends upon the presence of TAAR1 in the associated monoamine neurons. In addition to the neuronal monoamine transporters, amphetamine also inhibits both vesicular monoamine transporters, VMAT1 and VMAT2, as well as SLC1A1, SLC22A3, and SLC22A5. SLC1A1 is excitatory amino acid transporter 3 (EAAT3), a glutamate transporter located in neurons, SLC22A3 is an extraneuronal monoamine transporter that is present in astrocytes, and SLC22A5 is a high-affinity carnitine transporter. Amphetamine is known to strongly induce cocaine- and amphetamine-regulated transcript (CART) gene expression, a neuropeptide involved in feeding behavior, stress, and reward, which induces observable increases in neuronal development and survival "in vitro". The CART receptor has yet to be identified, but there is significant evidence that CART binds to a unique . Amphetamine also inhibits monoamine oxidases at very high doses, resulting in less monoamine and trace amine metabolism and consequently higher concentrations of synaptic monoamines. In humans, the only post-synaptic receptor at which amphetamine is known to bind is the receptor, where it acts as an agonist with low micromolar affinity.
The full profile of amphetamine's short-term drug effects in humans is mostly derived through increased cellular communication or neurotransmission of dopamine, serotonin, norepinephrine, epinephrine, histamine, CART peptides, endogenous opioids, adrenocorticotropic hormone, corticosteroids, and glutamate, which it affects through interactions with , , , , , , and possibly other biological targets. Amphetamine also activates seven human carbonic anhydrase enzymes, several of which are expressed in the human brain. Dextroamphetamine is a more potent agonist of than levoamphetamine. Consequently, dextroamphetamine produces greater stimulation than levoamphetamine, roughly three to four times more, but levoamphetamine has slightly stronger cardiovascular and peripheral effects. Dopamine. In certain brain regions, amphetamine increases the concentration of dopamine in the synaptic cleft. Amphetamine can enter the presynaptic neuron either through or by diffusing across the neuronal membrane directly. As a consequence of DAT uptake, amphetamine produces competitive reuptake inhibition at the transporter. Upon entering the presynaptic neuron, amphetamine activates which, through protein kinase A (PKA) and protein kinase C (PKC) signaling, causes DAT phosphorylation. Phosphorylation by either protein kinase can result in DAT internalization ( reuptake inhibition), but phosphorylation alone induces the reversal of dopamine transport through DAT (i.e., dopamine efflux). Amphetamine is also known to increase intracellular calcium, an effect which is associated with DAT phosphorylation through an unidentified Ca2+/calmodulin-dependent protein kinase (CAMK)-dependent pathway, in turn producing dopamine efflux. Through direct activation of G protein-coupled inwardly-rectifying potassium channels, reduces the firing rate of dopamine neurons, preventing a hyper-dopaminergic state.
Amphetamine is also a substrate for the presynaptic vesicular monoamine transporter, . Following amphetamine uptake at VMAT2, amphetamine induces the collapse of the vesicular pH gradient, which results in the release of dopamine molecules from synaptic vesicles into the cytosol via dopamine efflux through VMAT2. Subsequently, the cytosolic dopamine molecules are released from the presynaptic neuron into the synaptic cleft via reverse transport at . Norepinephrine. Similar to dopamine, amphetamine dose-dependently increases the level of synaptic norepinephrine, the direct precursor of epinephrine. Based upon neuronal expression, amphetamine is thought to affect norepinephrine analogously to dopamine. In other words, amphetamine induces TAAR1-mediated efflux and reuptake inhibition at phosphorylated , competitive NET reuptake inhibition, and norepinephrine release from . Serotonin. Amphetamine exerts analogous, yet less pronounced, effects on serotonin as on dopamine and norepinephrine. Amphetamine affects serotonin via and, like norepinephrine, is thought to phosphorylate via . Like dopamine, amphetamine has low, micromolar affinity at the human 5-HT1A receptor.
Other neurotransmitters, peptides, hormones, and enzymes. Acute amphetamine administration in humans increases endogenous opioid release in several brain structures in the reward system. Extracellular levels of glutamate, the primary excitatory neurotransmitter in the brain, have been shown to increase in the striatum following exposure to amphetamine. This increase in extracellular glutamate presumably occurs via the amphetamine-induced internalization of EAAT3, a glutamate reuptake transporter, in dopamine neurons. Amphetamine also induces the selective release of histamine from mast cells and efflux from histaminergic neurons through . Acute amphetamine administration can also increase adrenocorticotropic hormone and corticosteroid levels in blood plasma by stimulating the hypothalamic–pituitary–adrenal axis. In December 2017, the first study assessing the interaction between amphetamine and human carbonic anhydrase enzymes was published; of the eleven carbonic anhydrase enzymes it examined, it found that amphetamine potently activates seven, four of which are highly expressed in the human brain, with low nanomolar through low micromolar activating effects. Based upon preclinical research, cerebral carbonic anhydrase activation has cognition-enhancing effects; but, based upon the clinical use of carbonic anhydrase inhibitors, carbonic anhydrase activation in other tissues may be associated with adverse effects, such as ocular activation exacerbating glaucoma.
Pharmacokinetics. The oral bioavailability of amphetamine varies with gastrointestinal pH; it is well absorbed from the gut, and bioavailability is typically 90%. Amphetamine is a weak base with a p"K"a of 9.9; consequently, when the pH is basic, more of the drug is in its lipid soluble free base form, and more is absorbed through the lipid-rich cell membranes of the gut epithelium. Conversely, an acidic pH means the drug is predominantly in a water-soluble cationic (salt) form, and less is absorbed. Approximately of amphetamine circulating in the bloodstream is bound to plasma proteins. Following absorption, amphetamine readily distributes into most tissues in the body, with high concentrations occurring in cerebrospinal fluid and brain tissue. The half-lives of amphetamine enantiomers differ and vary with urine pH. At normal urine pH, the half-lives of dextroamphetamine and levoamphetamine are hours and hours, respectively. Highly acidic urine will reduce the enantiomer half-lives to 7 hours; highly alkaline urine will increase the half-lives up to 34 hours. The immediate-release and extended release variants of salts of both isomers reach peak plasma concentrations at 3 hours and 7 hours post-dose respectively. Amphetamine is eliminated via the kidneys, with of the drug being excreted unchanged at normal urinary pH. When the urinary pH is basic, amphetamine is in its free base form, so less is excreted. When urine pH is abnormal, the urinary recovery of amphetamine may range from a low of 1% to a high of 75%, depending mostly upon whether urine is too basic or acidic, respectively. Following oral administration, amphetamine appears in urine within 3 hours. Roughly 90% of ingested amphetamine is eliminated 3 days after the last oral dose.
CYP2D6, dopamine β-hydroxylase (DBH), flavin-containing monooxygenase 3 (FMO3), butyrate-CoA ligase (XM-ligase), and glycine "N"-acyltransferase (GLYAT) are the enzymes known to metabolize amphetamine or its metabolites in humans. Amphetamine has a variety of excreted metabolic products, including , , , benzoic acid, hippuric acid, norephedrine, and phenylacetone. Among these metabolites, the active sympathomimetics are , , and norephedrine. The main metabolic pathways involve aromatic para-hydroxylation, aliphatic alpha- and beta-hydroxylation, "N"-oxidation, "N"-dealkylation, and deamination. The known metabolic pathways, detectable metabolites, and metabolizing enzymes in humans include the following: Pharmacomicrobiomics. The human metagenome (i.e., the genetic composition of an individual and all microorganisms that reside on or within the individual's body) varies considerably between individuals. Since the total number of microbial and viral cells in the human body (over 100 trillion) greatly outnumbers human cells (tens of trillions), there is considerable potential for interactions between drugs and an individual's microbiome, including: drugs altering the composition of the human microbiome, drug metabolism by microbial enzymes modifying the drug's pharmacokinetic profile, and microbial drug metabolism affecting a drug's clinical efficacy and toxicity profile. The field that studies these interactions is known as pharmacomicrobiomics.
Similar to most biomolecules and other orally administered xenobiotics (i.e., drugs), amphetamine is predicted to undergo promiscuous metabolism by human gastrointestinal microbiota (primarily bacteria) prior to absorption into the blood stream. The first amphetamine-metabolizing microbial enzyme, tyramine oxidase from a strain of "E. coli" commonly found in the human gut, was identified in 2019. This enzyme was found to metabolize amphetamine, tyramine, and phenethylamine with roughly the same binding affinity for all three compounds. Related endogenous compounds. Amphetamine has a very similar structure and function to the endogenous trace amines, which are naturally occurring neuromodulator molecules produced in the human body and brain. Among this group, the most closely related compounds are phenethylamine, the parent compound of amphetamine, and , a structural isomer of amphetamine (i.e., it has an identical molecular formula). In humans, phenethylamine is produced directly from by the aromatic amino acid decarboxylase (AADC) enzyme, which converts into dopamine as well. In turn, is metabolized from phenethylamine by phenylethanolamine "N"-methyltransferase, the same enzyme that metabolizes norepinephrine into epinephrine. Like amphetamine, both phenethylamine and regulate monoamine neurotransmission via ; unlike amphetamine, both of these substances are broken down by monoamine oxidase B, and therefore have a shorter half-life than amphetamine.
Chemistry. Amphetamine is a methyl homolog of the mammalian neurotransmitter phenethylamine with the chemical formula . The carbon atom adjacent to the primary amine is a stereogenic center, and amphetamine is composed of a racemic 1:1 mixture of two enantiomers. This racemic mixture can be separated into its optical isomers: levoamphetamine and dextroamphetamine. At room temperature, the pure free base of amphetamine is a mobile, colorless, and volatile liquid with a characteristically strong amine odor, and acrid, burning taste. Frequently prepared solid salts of amphetamine include amphetamine adipate, aspartate, hydrochloride, phosphate, saccharate, sulfate, and tannate. Dextroamphetamine sulfate is the most common enantiopure salt. Amphetamine is also the parent compound of its own structural class, which includes a number of psychoactive derivatives. In organic chemistry, amphetamine is an excellent chiral ligand for the stereoselective synthesis of . Substituted derivatives. The substituted derivatives of amphetamine, or "substituted amphetamines", are a broad range of chemicals that contain amphetamine as a "backbone"; specifically, this chemical class includes derivative compounds that are formed by replacing one or more hydrogen atoms in the amphetamine core structure with substituents. The class includes amphetamine itself, stimulants like methamphetamine, serotonergic empathogens like MDMA, and decongestants like ephedrine, among other subgroups.
Synthesis. Since the first preparation was reported in 1887, numerous synthetic routes to amphetamine have been developed. The most common route of both legal and illicit amphetamine synthesis employs a non-metal reduction known as the Leuckart reaction (method 1). In the first step, a reaction between phenylacetone and formamide, either using additional formic acid or formamide itself as a reducing agent, yields . This intermediate is then hydrolyzed using hydrochloric acid, and subsequently basified, extracted with organic solvent, concentrated, and distilled to yield the free base. The free base is then dissolved in an organic solvent, sulfuric acid added, and amphetamine precipitates out as the sulfate salt. A number of chiral resolutions have been developed to separate the two enantiomers of amphetamine. For example, racemic amphetamine can be treated with to form a diastereoisomeric salt which is fractionally crystallized to yield dextroamphetamine. Chiral resolution remains the most economical method for obtaining optically pure amphetamine on a large scale. In addition, several enantioselective syntheses of amphetamine have been developed. In one example, optically pure is condensed with phenylacetone to yield a chiral Schiff base. In the key step, this intermediate is reduced by catalytic hydrogenation with a transfer of chirality to the carbon atom alpha to the amino group. Cleavage of the benzylic amine bond by hydrogenation yields optically pure dextroamphetamine.
A large number of alternative synthetic routes to amphetamine have been developed based on classic organic reactions. One example is the Friedel–Crafts alkylation of benzene by allyl chloride to yield beta chloropropylbenzene which is then reacted with ammonia to produce racemic amphetamine (method 2). Another example employs the Ritter reaction (method 3). In this route, allylbenzene is reacted acetonitrile in sulfuric acid to yield an organosulfate which in turn is treated with sodium hydroxide to give amphetamine via an acetamide intermediate. A third route starts with which through a double alkylation with methyl iodide followed by benzyl chloride can be converted into acid. This synthetic intermediate can be transformed into amphetamine using either a Hofmann or Curtius rearrangement (method 4). A significant number of amphetamine syntheses feature a reduction of a nitro, imine, oxime, or other nitrogen-containing functional groups. In one such example, a Knoevenagel condensation of benzaldehyde with nitroethane yields . The double bond and nitro group of this intermediate is reduced using either catalytic hydrogenation or by treatment with lithium aluminium hydride (method 5). Another method is the reaction of phenylacetone with ammonia, producing an imine intermediate that is reduced to the primary amine using hydrogen over a palladium catalyst or lithium aluminum hydride (method 6).
Detection in body fluids. Amphetamine is frequently measured in urine or blood as part of a drug test for sports, employment, poisoning diagnostics, and forensics. Techniques such as immunoassay, which is the most common form of amphetamine test, may cross-react with a number of sympathomimetic drugs. Chromatographic methods specific for amphetamine are employed to prevent false positive results. Chiral separation techniques may be employed to help distinguish the source of the drug, whether prescription amphetamine, prescription amphetamine prodrugs, (e.g., selegiline), over-the-counter drug products that contain levomethamphetamine, or illicitly obtained substituted amphetamines. Several prescription drugs produce amphetamine as a metabolite, including benzphetamine, clobenzorex, famprofazone, fenproporex, lisdexamfetamine, mesocarb, methamphetamine, prenylamine, and selegiline, among others. These compounds may produce positive results for amphetamine on drug tests. Amphetamine is generally only detectable by a standard drug test for approximately 24 hours, although a high dose may be detectable for days.
For the assays, a study noted that an enzyme multiplied immunoassay technique (EMIT) assay for amphetamine and methamphetamine may produce more false positives than liquid chromatography–tandem mass spectrometry. Gas chromatography–mass spectrometry (GC–MS) of amphetamine and methamphetamine with the derivatizing agent chloride allows for the detection of methamphetamine in urine. GC–MS of amphetamine and methamphetamine with the chiral derivatizing agent Mosher's acid chloride allows for the detection of both dextroamphetamine and dextromethamphetamine in urine. Hence, the latter method may be used on samples that test positive using other methods to help distinguish between the various sources of the drug. History, society, and culture. Amphetamine was first synthesized in 1887 in Germany by Romanian chemist Lazăr Edeleanu who named it "phenylisopropylamine"; its stimulant effects remained unknown until 1927, when it was independently resynthesized by Gordon Alles and reported to have sympathomimetic properties. Amphetamine had no medical use until late 1933, when Smith, Kline and French began selling it as an inhaler under the brand name Benzedrine as a decongestant. Benzedrine sulfate was introduced 3 years later and was used to treat a wide variety of medical conditions, including narcolepsy, obesity, low blood pressure, low libido, and chronic pain, among others. During World War II, amphetamine and methamphetamine were used extensively by both the Allied and Axis forces for their stimulant and performance-enhancing effects. As the addictive properties of the drug became known, governments began to place strict controls on the sale of amphetamine. For example, during the early 1970s in the United States, amphetamine became a schedule II controlled substance under the Controlled Substances Act. In spite of strict government controls, amphetamine has been used legally or illicitly by people from a variety of backgrounds, including authors, musicians, mathematicians, and athletes.
Amphetamine is illegally synthesized in clandestine labs and sold on the black market, primarily in European countries. Among European Union (EU) member states 11.9 million adults of ages have used amphetamine or methamphetamine at least once in their lives and 1.7 million have used either in the last year. During 2012, approximately 5.9 metric tons of illicit amphetamine were seized within EU member states; the "street price" of illicit amphetamine within the EU ranged from per gram during the same period. Outside Europe, the illicit market for amphetamine is much smaller than the market for methamphetamine and MDMA. Legal status. As a result of the United Nations 1971 Convention on Psychotropic Substances, amphetamine became a schedule II controlled substance, as defined in the treaty, in all 183 state parties. Consequently, it is heavily regulated in most countries. Some countries, such as South Korea and Japan, have banned substituted amphetamines even for medical use. In other nations, such as Brazil (class A3), Canada (schedule I drug), the Netherlands (List I drug), the United States (schedule II drug), Australia (schedule 8), Thailand (category 1 narcotic), and United Kingdom (class B drug), amphetamine is in a restrictive national drug schedule that allows for its use as a medical treatment.
Pharmaceutical products. Several currently marketed amphetamine formulations contain both enantiomers, including those marketed under the brand names Adderall, Adderall XR, Mydayis, Adzenys ER, , Dyanavel XR, Evekeo, and Evekeo ODT. Of those, Evekeo (including Evekeo ODT) is the only product containing only racemic amphetamine (as amphetamine sulfate), and is therefore the only one whose active moiety can be accurately referred to simply as "amphetamine". Dextroamphetamine, marketed under the brand names Dexedrine and Zenzedi, is the only enantiopure amphetamine product currently available. A prodrug form of dextroamphetamine, lisdexamfetamine, is also available and is marketed under the brand name Vyvanse. As it is a prodrug, lisdexamfetamine is structurally different from dextroamphetamine, and is inactive until it metabolizes into dextroamphetamine. The free base of racemic amphetamine was previously available as Benzedrine, Psychedrine, and Sympatedrine. Levoamphetamine was previously available as Cydril. Many current amphetamine pharmaceuticals are salts due to the comparatively high volatility of the free base. However, oral suspension and orally disintegrating tablet (ODT) dosage forms composed of the free base were introduced in 2015 and 2016, respectively. Some of the current brands and their generic equivalents are listed below.
Asynchronous communication In telecommunications, asynchronous communication is transmission of data, generally without the use of an external clock signal, where data can be transmitted intermittently rather than in a steady stream. Any timing required to recover data from the communication symbols is encoded within the symbols. The most significant aspect of asynchronous communications is that data is not transmitted at regular intervals, thus making possible variable bit rate, and that the transmitter and receiver clock generators do not have to be exactly synchronized all the time. In asynchronous transmission, data is sent one byte at a time and each byte is preceded by start and stop bits. Physical layer. In asynchronous serial communication in the physical protocol layer, the data blocks are code words of a certain word length, for example octets (bytes) or ASCII characters, delimited by start bits and stop bits. A variable length space can be inserted between the code words. No bit synchronization signal is required. This is sometimes called character oriented communication. Examples include MNP2 and modems older than V.2.
Data link layer and higher. Asynchronous communication at the data link layer or higher protocol layers is known as statistical multiplexing, for example Asynchronous Transfer Mode (ATM). In this case, the asynchronously transferred blocks are called data packets, for example ATM cells. The opposite is circuit switched communication, which provides constant bit rate, for example ISDN and SONET/SDH. The packets may be encapsulated in a data frame, with a frame synchronization bit sequence indicating the start of the frame, and sometimes also a bit synchronization bit sequence, typically 01010101, for identification of the bit transition times. Note that at the physical layer, this is considered as synchronous serial communication. Examples of packet mode data link protocols that can be/are transferred using synchronous serial communication are the HDLC, Ethernet, PPP and USB protocols. Application layer. An asynchronous communication service or application does not require a constant bit rate. Examples are file transfer, email and the World Wide Web. An example of the opposite, a synchronous communication service, is realtime streaming media, for example IP telephony, IPTV and video conferencing.
Electronically mediated communication. Electronically mediated communication often happens asynchronously in that the participants do not communicate concurrently. Examples include email and bulletin-board systems, where participants send or post messages at different times than they read them. The term "asynchronous communication" acquired currency in the field of online learning, where teachers and students often exchange information asynchronously instead of synchronously (that is, simultaneously), as they would in face-to-face or in telephone conversations.
Artillery Artillery refers to ranged weapons that launch munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during sieges, and led to heavy, fairly immobile siege engines. As technology improved, lighter, more mobile field artillery cannons developed for battlefield use. This development continues today; modern self-propelled artillery vehicles are highly mobile weapons of great versatility generally providing the largest share of an army's total firepower. Originally, the word "artillery" referred to any group of soldiers primarily armed with some form of manufactured weapon or armour. Since the introduction of gunpowder and cannon, "artillery" has largely meant cannon, and in contemporary usage, usually refers to shell-firing guns, howitzers, and mortars (collectively called "barrel artillery", "cannon artillery" or "gun artillery") and rocket artillery. In common speech, the word "artillery" is often used to refer to individual devices, along with their accessories and fittings, although these assemblages are more properly called "equipment". However, there is no generally recognized generic term for a gun, howitzer, mortar, and so forth: the United States uses "artillery piece", but most English-speaking armies use "gun" and "mortar". The projectiles fired are typically either "shot" (if solid) or "shell" (if not solid). Historically, variants of solid shot including canister, chain shot and grapeshot were also used. "Shell" is a widely used generic term for a projectile, which is a component of munitions.
By association, artillery may also refer to the arm of service that customarily operates such engines. In some armies, the artillery arm has operated field, coastal, anti-aircraft, and anti-tank artillery; in others these have been separate arms, and with some nations coastal has been a naval or marine responsibility. In the 20th century, target acquisition devices (such as radar) and techniques (such as sound ranging and flash spotting) emerged, primarily for artillery. These are usually utilized by one or more of the artillery arms. The widespread adoption of indirect fire in the early 20th century introduced the need for specialist data for field artillery, notably survey and meteorological, and in some armies, provision of these are the responsibility of the artillery arm. The majority of combat deaths in the Napoleonic Wars, World War I, and World War II were caused by artillery. In 1944, Joseph Stalin said in a speech that artillery was "the god of war". Artillery piece. Although not called by that name, siege engines performing the role recognizable as artillery have been employed in warfare since antiquity. The first known catapult was developed in Syracuse in 399 BC. Until the introduction of gunpowder into western warfare, artillery was dependent upon mechanical energy, which not only severely limited the kinetic energy of the projectiles, but also required the construction of very large engines to accumulate sufficient energy. A 1st-century BC Roman catapult launching stones achieved a kinetic energy of 16 kilojoules, compared to a mid-19th-century 12-pounder gun, which fired a round, with a kinetic energy of 240 kilojoules, or a 20th-century US battleship that fired a projectile from its main battery with an energy level surpassing 350 megajoules.
From the Middle Ages through most of the modern era, artillery pieces on land were moved by horse-drawn gun carriages. In the contemporary era, artillery pieces and their crew relied on wheeled or tracked vehicles as transportation. These land versions of artillery were dwarfed by railway guns; the largest of these large-calibre guns ever conceived – Project Babylon of the Supergun affair – was theoretically capable of putting a satellite into orbit. Artillery used by naval forces has also changed significantly, with missiles generally replacing guns in surface warfare. Over the course of military history, projectiles were manufactured from a wide variety of materials, into a wide variety of shapes, using many different methods in which to target structural/defensive works and inflict enemy casualties. The engineering applications for ordnance delivery have likewise changed significantly over time, encompassing some of the most complex and advanced technologies in use today. In some armies, the weapon of artillery is the projectile, not the equipment that fires it. The process of delivering fire onto the target is called gunnery. The actions involved in operating an artillery piece are collectively called "serving the gun" by the "detachment" or gun crew, constituting either direct or indirect artillery fire. The manner in which gunnery crews (or formations) are employed is called artillery support. At different periods in history, this may refer to weapons designed to be fired from ground-, sea-, and even air-based weapons platforms.
Crew. Some armed forces use the term "gunners" for the soldiers and sailors with the primary function of using artillery. The gunners and their guns are usually grouped in teams called either "crews" or "detachments". Several such crews and teams with other functions are combined into a unit of artillery, usually called a battery, although sometimes called a company. In gun detachments, each role is numbered, starting with "1" the Detachment Commander, and the highest number being the Coverer, the second-in-command. "Gunner" is also the lowest rank, and junior non-commissioned officers are "Bombardiers" in some artillery arms. Batteries are roughly equivalent to a company in the infantry, and are combined into larger military organizations for administrative and operational purposes, either battalions or regiments, depending on the army. These may be grouped into brigades; the Russian army also groups some brigades into artillery divisions, and the People's Liberation Army has artillery corps. The term "artillery" also designates a combat arm of most military services when used organizationally to describe units and formations of the national armed forces that operate the weapons.
Tactics. During military operations, field artillery has the role of providing support to other arms in combat or of attacking targets, particularly in-depth. Broadly, these effects fall into two categories, aiming either to suppress or neutralize the enemy, or to cause casualties, damage, and destruction. This is mostly achieved by delivering high-explosive munitions to suppress, or inflict casualties on the enemy from casing fragments and other debris and from blast, or by destroying enemy positions, equipment, and vehicles. Non-lethal munitions, notably smoke, can also suppress or neutralize the enemy by obscuring their view. Fire may be directed by an artillery observer or another observer, including crewed and uncrewed aircraft, or called onto map coordinates. Military doctrine has had a significant influence on the core engineering design considerations of artillery ordnance through its history, in seeking to achieve a balance between the delivered volume of fire with ordnance mobility. However, during the modern period, the consideration of protecting the gunners also arose due to the late-19th-century introduction of the new generation of infantry weapons using conoidal bullet, better known as the Minié ball, with a range almost as long as that of field artillery.
The gunners' increasing proximity to and participation in direct combat against other combat arms and attacks by aircraft made the introduction of a gun shield necessary. The problems of how to employ a fixed or horse-towed gun in mobile warfare necessitated the development of new methods of transporting the artillery into combat. Two distinct forms of artillery were developed: the towed gun, used primarily to attack or defend a fixed-line; and the self-propelled gun, intended to accompany a mobile force and to provide continuous fire support and/or suppression. These influences have guided the development of artillery ordnance, systems, organizations, and operations until the present, with artillery systems capable of providing support at ranges from as little as 100 m to the intercontinental ranges of ballistic missiles. The only combat in which artillery is unable to take part is close-quarters combat, with the possible exception of artillery reconnaissance teams. Etymology. The word as used in the current context originated in the Middle Ages. One suggestion is that it comes from French "atelier", meaning the place where manual work is done.
Another suggestion is that it originates from the 13th century and the Old French "artillier", designating craftsmen and manufacturers of all materials and warfare equipments (spears, swords, armor, war machines); and, for the next 250 years, the sense of the word "artillery" covered all forms of military weapons. Hence, the naming of the Honourable Artillery Company, which was essentially an infantry unit until the 19th century. Another suggestion is that it comes from the Italian "arte de tirare" (art of shooting), coined by one of the first theorists on the use of artillery, Niccolò Tartaglia. The term was used by Girolamo Ruscelli (died 1566) in his "Precepts of Modern Militia" published posthumously in 1572. History. Mechanical systems used for throwing ammunition in ancient warfare, also known as "engines of war", like the catapult, onager, trebuchet, and ballista, are also referred to by military historians as artillery. Medieval. During medieval times, more types of artillery were developed, most notably the counterweight trebuchet. Traction trebuchets, using manpower to launch projectiles, have been used in ancient China since the 4th century as anti-personnel weapons. The much more powerful counterweight trebuchet was invented in the eastern Mediterranean region in the 12th century, with the earliest definite attestation in 1187.
Invention of gunpowder. Early Chinese artillery had vase-like shapes. This includes the "long range awe inspiring" cannon dated from 1350 and found in the 14th century Ming dynasty treatise "Huolongjing". With the development of better metallurgy techniques, later cannons abandoned the vase shape of early Chinese artillery. This change can be seen in the bronze "thousand ball thunder cannon", an early example of field artillery. These small, crude weapons diffused into the Middle East (the "madfaa") and reached Europe in the 13th century, in a very limited manner. In Asia, Mongols adopted the Chinese artillery and used it effectively in the great conquest. By the late 14th century, Chinese rebels used organized artillery and cavalry to push Mongols out. As small smooth-bore barrels, these were initially cast in iron or bronze around a core, with the first drilled bore ordnance recorded in operation near Seville in 1247. They fired lead, iron, or stone balls, sometimes large arrows and on occasions simply handfuls of whatever scrap came to hand. During the Hundred Years' War, these weapons became more common, initially as the bombard and later the cannon. Cannons were always muzzle-loaders. While there were many early attempts at breech-loading designs, a lack of engineering knowledge rendered these even more dangerous to use than muzzle-loaders.
Expansion of use. In 1415, the Portuguese invaded the Mediterranean port town of Ceuta. While it is difficult to confirm the use of firearms in the siege of the city, it is known the Portuguese defended it thereafter with firearms, namely "bombardas", "colebratas", and "falconetes". In 1419, Sultan Abu Sa'id led an army to reconquer the fallen city, and Marinids brought cannons and used them in the assault on Ceuta. Finally, hand-held firearms and riflemen appear in Morocco, in 1437, in an expedition against the people of Tangiers. It is clear these weapons had developed into several different forms, from small guns to large artillery pieces. The artillery revolution in Europe caught on during the Hundred Years' War and changed the way that battles were fought. In the preceding decades, the English had even used a gunpowder-like weapon in military campaigns against the Scottish. However, at this time, the cannons used in battle were very small and not particularly powerful. Cannons were only useful for the defense of a castle, as demonstrated at Breteuil in 1356, when the besieged English used a cannon to destroy an attacking French assault tower. By the end of the 14th century, cannons were only powerful enough to knock in roofs, and could not penetrate castle walls.
However, a major change occurred between 1420 and 1430, when artillery became much more powerful and could now batter strongholds and fortresses quite efficiently. The English, French, and Burgundians all advanced in military technology, and as a result the traditional advantage that went to the defense in a siege was lost. Cannons during this period were elongated, and the recipe for gunpowder was improved to make it three times as powerful as before. These changes led to the increased power in the artillery weapons of the time. Joan of Arc encountered gunpowder weaponry several times. When she led the French against the English at the Battle of Tourelles, in 1430, she faced heavy gunpowder fortifications, and yet her troops prevailed in that battle. In addition, she led assaults against the English-held towns of Jargeau, Meung, and Beaugency, all with the support of large artillery units. When she led the assault on Paris, Joan faced stiff artillery fire, especially from the suburb of St. Denis, which ultimately led to her defeat in this battle. In April 1430, she went to battle against the Burgundians, whose support was purchased by the English. At this time, the Burgundians had the strongest and largest gunpowder arsenal among the European powers, and yet the French, under Joan of Arc's leadership, were able to beat back the Burgundians and defend themselves. As a result, most of the battles of the Hundred Years' War that Joan of Arc participated in were fought with gunpowder artillery.
The army of Mehmet the Conqueror, which conquered Constantinople in 1453, included both artillery and foot soldiers armed with gunpowder weapons. The Ottomans brought to the siege sixty-nine guns in fifteen separate batteries and trained them at the walls of the city. The barrage of Ottoman cannon fire lasted forty days, and they are estimated to have fired 19,320 times. Artillery also played a decisive role in the Battle of St. Jakob an der Birs of 1444. Early cannon were not always reliable; King James II of Scotland was killed by the accidental explosion of one of his own cannon, imported from Flanders, at the siege of Roxburgh Castle in 1460. The able use of artillery supported to a large measure the expansion and defense of the Portuguese Empire, as it was a necessary tool that allowed the Portuguese to face overwhelming odds both on land and sea from Morocco to Asia. In great sieges and in sea battles, the Portuguese demonstrated a level of proficiency in the use of artillery after the beginning of the 16th century unequalled by contemporary European neighbours, in part due to the experience gained in intense fighting in Morocco, which served as a proving ground for artillery and its practical application, and made Portugal a forerunner in gunnery for decades. During the reign of King Manuel (1495–1521) at least 2017 cannon were sent to Morocco for garrison defense, with more than 3000 cannon estimated to have been required during that 26-year period. An especially noticeable division between siege guns and anti-personnel guns enhanced the use and effectiveness of Portuguese firearms above contemporary powers, making cannon the most essential element in the Portuguese arsenal.
The three major classes of Portuguese artillery were anti-personnel guns with a high borelength (including: "rebrodequim", "berço", "falconete", "falcão", "sacre", "áspide", "cão", "serpentina" and "passavolante"); bastion guns which could batter fortifications ("camelete", "leão", "pelicano", "basilisco", "águia", "camelo", "roqueira", "urso"); and howitzers that fired large stone cannonballs in an elevated arch, weighted up to 4000 pounds and could fire incendiary devices, such as a hollow iron ball filled with pitch and fuse, designed to be fired at close range and burst on contact. The most popular in Portuguese arsenals was the "berço", a 5 cm, one pounder bronze breech-loading cannon that weighted 150 kg with an effective range of 600 meters. A tactical innovation the Portuguese introduced in fort defense was the use of combinations of projectiles against massed assaults. Although canister shot had been developed in the early 15th century, the Portuguese were the first to employ it extensively, and Portuguese engineers invented a canister round which consisted of a thin lead case filled with iron pellets, that broke up at the muzzle and scattered its contents in a narrow pattern. An innovation which Portugal adopted in advance of other European powers was fuse-delayed action shells, and were commonly used in 1505. Although dangerous, their effectiveness meant a sixth of all rounds used by the Portuguese in Morocco were of the fused-shell variety.
The new Ming Dynasty established the "Divine Engine Battalion" (神机营), which specialized in various types of artillery. Light cannons and cannons with multiple volleys were developed. In a campaign to suppress a local minority rebellion near today's Burmese border, "the Ming army used a 3-line method of arquebuses/muskets to destroy an elephant formation". When the Portuguese and Spanish arrived at Southeast Asia, they found that the local kingdoms were already using cannons. Portuguese and Spanish invaders were unpleasantly surprised and even outgunned on occasion. Duarte Barbosa ca. 1514 said that the inhabitants of Java were great masters in casting artillery and very good artillerymen. They made many one-pounder cannons (cetbang or rentaka), long muskets, "spingarde" (arquebus), "schioppi" (hand cannon), Greek fire, guns (cannons), and other fire-works. In all aspects the Javanese were considered excellent in casting artillery, and in the knowledge of using it. In 1513, the Javanese fleet led by Pati Unus sailed to attack Portuguese Malacca "with much artillery made in Java, for the Javanese are skilled in founding and casting, and in all works in iron, over and above what they have in India". By the early 16th century, the Javanese had already started locally-producing large guns, which were dubbed "sacred cannon[s]" or "holy cannon[s]" and have survived up to the present day - though in limited numbers. These cannons varied between 180 and 260 pounders, weighing anywhere between 3–8 tons, measuring between 3–6 m.
Between 1593 and 1597, about 200,000 Korean and Chinese troops which fought against Japan in Korea actively used heavy artillery in both siege and field combat. Korean forces mounted artillery in ships as naval guns, providing an advantage against Japanese navy which used "Kunikuzushi" (国崩し – Japanese breech-loading swivel gun) and "Ōzutsu" (大筒 – large size Tanegashima) as their largest firearms. In the 16th century Ottoman Empire, Humbaracıs were founded. Smoothbores. Bombards were of value mainly in sieges. A famous Turkish example used at the siege of Constantinople in 1453 weighed 19 tons, took 200 men and sixty oxen to emplace, and could fire just seven times a day. The Fall of Constantinople was perhaps "the first event of supreme importance whose result was determined by the use of artillery" when the huge bronze cannons of Mehmed II breached the city's walls, ending the Byzantine Empire, according to Sir Charles Oman. Bombards developed in Europe were massive smoothbore weapons distinguished by their lack of a field carriage, immobility once emplaced, highly individual design, and noted unreliability (in 1460 James II, King of Scots, was killed when one exploded at the siege of Roxburgh). Their large size precluded the barrels being cast and they were constructed out of metal staves or rods bound together with hoops like a barrel, giving their name to the gun barrel.
The use of the word "cannon" marks the introduction in the 15th century of a dedicated field carriage with axle, trail and animal-drawn limber—this produced mobile field pieces that could move and support an army in action, rather than being found only in the siege and static defenses. The reduction in the size of the barrel was due to improvements in both iron technology and gunpowder manufacture, while the development of trunnions—projections at the side of the cannon as an integral part of the cast—allowed the barrel to be fixed to a more movable base, and also made raising or lowering the barrel much easier. The first land-based mobile weapon is usually credited to Jan Žižka, who deployed his oxen-hauled cannon during the Hussite Wars of Bohemia (1418–1424). However, cannons were still large and cumbersome. With the rise of musketry in the 16th century, cannon were largely (though not entirely) displaced from the battlefield—the cannon were too slow and cumbersome to be used and too easily lost to a rapid enemy advance.
The combining of shot and powder into a single unit, a cartridge, occurred in the 1620s with a simple fabric bag, and was quickly adopted by all nations. It speeded loading and made it safer, but unexpelled bag fragments were an additional fouling in the gun barrel and a new tool—a worm—was introduced to remove them. Gustavus Adolphus is identified as the general who made cannon an effective force on the battlefield—pushing the development of much lighter and smaller weapons and deploying them in far greater numbers than previously. The outcome of battles was still determined by the clash of infantry. Shells, explosive-filled fused projectiles, were in use by the 15th century. The development of specialized pieces—shipboard artillery, howitzers and mortars—was also begun in this period. More esoteric designs, like the multi-barrel "ribauldequin" (known as "organ guns"), were also produced. The 1650 book by Kazimierz Siemienowicz "Artis Magnae Artilleriae pars prima" was one of the most important contemporary publications on the subject of artillery. For over two centuries this work was used in Europe as a basic artillery manual.
One of the most significant effects of artillery during this period was however somewhat more indirect—by easily reducing to rubble any medieval-type fortification or city wall (some which had stood since Roman times), it abolished millennia of siege-warfare strategies and styles of fortification building. This led, among other things, to a frenzy of new bastion-style fortifications to be built all over Europe and in its colonies, but also had a strong integrating effect on emerging nation-states, as kings were able to use their newfound artillery superiority to force any local dukes or lords to submit to their will, setting the stage for the absolutist kingdoms to come. Modern rocket artillery can trace its heritage back to the Mysorean rockets of Mysore. Their first recorded use was in 1780 during the battles of the Second, Third and Fourth Mysore Wars. The wars fought between the British East India Company and the Kingdom of Mysore in India made use of the rockets as a weapon. In the Battle of Pollilur, the Siege of Seringapatam (1792) and in Battle of Seringapatam in 1799, these rockets were used with considerable effect against the British. After the wars, several Mysore rockets were sent to England, but experiments with heavier payloads were unsuccessful. In 1804 William Congreve, considering the Mysorian rockets to have too short a range (less than 1,000 yards) developed rockets in numerous sizes with ranges up to 3,000 yards and eventually utilizing iron casing as the Congreve rocket which were used effectively during the Napoleonic Wars and the War of 1812.
Napoleonic. With the Napoleonic Wars, artillery experienced changes in both physical design and operation. Rather than being overseen by "mechanics", artillery was viewed as its own service branch with the capability of dominating the battlefield. The success of the French artillery companies was at least in part due to the presence of specially trained artillery officers leading and coordinating during the chaos of battle. Napoleon, himself a former artillery officer, perfected the tactic of massed artillery batteries unleashed upon a critical point in his enemies' line as a prelude to a decisive infantry and cavalry assault. Physically, cannons continued to become smaller and lighter. During the Seven Years War, King Frederick II of Prussia used these advances to deploy horse artillery that could move throughout the battlefield. Frederick also introduced the reversible iron ramrod, which was much more resistant to breakage than older wooden designs. The reversibility aspect also helped increase the rate of fire, since a soldier would no longer have to worry about what end of the ramrod they were using.
Jean-Baptiste de Gribeauval, a French artillery engineer, introduced the standardization of cannon design in the mid-18th century. He developed a 6-inch (150 mm) field howitzer whose gun barrel, carriage assembly and ammunition specifications were made uniform for all French cannons. The standardized interchangeable parts of these cannons down to the nuts, bolts and screws made their mass production and repair much easier. While the Gribeauval system made for more efficient production and assembly, the carriages used were heavy and the gunners were forced to march on foot (instead of riding on the limber and gun as in the British system). Each cannon was named for the weight of its projectiles, giving us variants such as 4, 8, and 12, indicating the weight in pounds. The projectiles themselves included solid balls or canister containing lead bullets or other material. These canister shots acted as massive shotguns, peppering the target with hundreds of projectiles at close range. The solid balls, known as round shot, was most effective when fired at shoulder-height across a flat, open area. The ball would tear through the ranks of the enemy or bounce along the ground breaking legs and ankles.
Modern. The development of modern artillery occurred in the mid to late 19th century as a result of the convergence of various improvements in the underlying technology. Advances in metallurgy allowed for the construction of breech-loading rifled guns that could fire at a much greater muzzle velocity. After the British artillery was shown up in the Crimean War as having barely changed since the Napoleonic Wars, the industrialist William Armstrong was awarded a contract by the government to design a new piece of artillery. Production started in 1855 at the Elswick Ordnance Company and the Royal Arsenal at Woolwich, and the outcome was the revolutionary Armstrong Gun, which marked the birth of modern artillery. Three of its features particularly stand out. First, the piece was rifled, which allowed for a much more accurate and powerful action. Although rifling had been tried on small arms since the 15th century, the necessary machinery to accurately rifle artillery was not available until the mid-19th century. Martin von Wahrendorff, and Joseph Whitworth independently produced rifled cannon in the 1840s, but it was Armstrong's gun that was first to see widespread use during the Crimean War. The cast iron shell of the Armstrong gun was similar in shape to a Minié ball and had a thin lead coating which made it fractionally larger than the gun's bore and which engaged with the gun's rifling grooves to impart spin to the shell. This spin, together with the elimination of windage as a result of the tight fit, enabled the gun to achieve greater range and accuracy than existing smooth-bore muzzle-loaders with a smaller powder charge.
His gun was also a breech-loader. Although attempts at breech-loading mechanisms had been made since medieval times, the essential engineering problem was that the mechanism could not withstand the explosive charge. It was only with the advances in metallurgy and precision engineering capabilities during the Industrial Revolution that Armstrong was able to construct a viable solution. The gun combined all the properties that make up an effective artillery piece. The gun was mounted on a carriage in such a way as to return the gun to firing position after the recoil. What made the gun really revolutionary lay in the technique of the construction of the gun barrel that allowed it to withstand much more powerful explosive forces. The "built-up" method involved assembling the barrel with wrought-iron (later mild steel was used) tubes of successively smaller diameter. The tube would then be heated to allow it to expand and fit over the previous tube. When it cooled the gun would contract although not back to its original size, which allowed an even pressure along the walls of the gun which was directed inward against the outward forces that the gun's firing exerted on the barrel.
Another innovative feature, more usually associated with 20th-century guns, was what Armstrong called its "grip", which was essentially a squeeze bore; the 6 inches of the bore at the muzzle end was of slightly smaller diameter, which centered the shell before it left the barrel and at the same time slightly swaged down its lead coating, reducing its diameter and slightly improving its ballistic qualities. Armstrong's system was adopted in 1858, initially for "special service in the field" and initially he produced only smaller artillery pieces, 6-pounder (2.5 in/64 mm) mountain or light field guns, 9-pounder (3 in/76 mm) guns for horse artillery, and 12-pounder (3 inches /76 mm) field guns. The first cannon to contain all 'modern' features is generally considered to be the French 75 of 1897. The gun used cased ammunition, was breech-loading, had modern sights, and a self-contained firing mechanism. It was the first field gun to include a hydro-pneumatic recoil mechanism, which kept the gun's trail and wheels perfectly still during the firing sequence. Since it did not need to be re-aimed after each shot, the crew could fire as soon as the barrel returned to its resting position. In typical use, the French 75 could deliver fifteen rounds per minute on its target, either shrapnel or melinite high-explosive, up to about 5 miles (8,500 m) away. Its firing rate could even reach close to 30 rounds per minute, albeit only for a very short time and with a highly experienced crew. These were rates that contemporary bolt action rifles could not match.
Indirect fire. Indirect fire, the firing of a projectile without relying on direct line of sight between the gun and the target, possibly dates back to the 16th century. Early battlefield use of indirect fire may have occurred at Paltzig in July 1759, when the Russian artillery fired over the tops of trees, and at the Battle of Waterloo, where a battery of the Royal Horse Artillery fired shrapnel indirectly against advancing French troops. In 1882, Russian Lieutenant Colonel KG Guk published "Indirect Fire for Field Artillery", which provided a practical method of using aiming points for indirect fire by describing, "all the essentials of aiming points, crest clearance, and corrections to fire by an observer". A few years later, the Richtfläche (lining-plane) sight was invented in Germany and provided a means of indirect laying in azimuth, complementing the clinometers for indirect laying in elevation which already existed. Despite conservative opposition within the German army, indirect fire was adopted as doctrine by the 1890s. In the early 1900s, Goertz in Germany developed an optical sight for azimuth laying. It quickly replaced the lining-plane; in English, it became the 'Dial Sight' (UK) or 'Panoramic Telescope' (US).
The British halfheartedly experimented with indirect fire techniques since the 1890s, but with the onset of the Boer War, they were the first to apply the theory in practice in 1899, although they had to improvise without a lining-plane sight. In the next 15 years leading up to World War I, the techniques of indirect fire became available for all types of artillery. Indirect fire was the defining characteristic of 20th-century artillery and led to undreamt of changes in the amount of artillery, its tactics, organisation, and techniques, most of which occurred during World War I. An implication of indirect fire and improving guns was increasing range between gun and target, this increased the time of flight and the vertex of the trajectory. The result was decreasing accuracy (the increasing distance between the target and the mean point of impact of the shells aimed at it) caused by the increasing effects of non-standard conditions. Indirect firing data was based on standard conditions including a specific muzzle velocity, zero wind, air temperature and density, and propellant temperature. In practice, this standard combination of conditions almost never existed, they varied throughout the day and day to day, and the greater the time of flight, the greater the inaccuracy. An added complication was the need for survey to accurately fix the coordinates of the gun position and provide accurate orientation for the guns. Of course, targets had to be accurately located, but by 1916, air photo interpretation techniques enabled this, and ground survey techniques could sometimes be used.
In 1914, the methods of correcting firing data for the actual conditions were often convoluted, and the availability of data about actual conditions was rudimentary or non-existent, the assumption was that fire would always be ranged (adjusted). British heavy artillery worked energetically to progressively solve all these problems from late 1914 onwards, and by early 1918, had effective processes in place for both field and heavy artillery. These processes enabled 'map-shooting', later called 'predicted fire'; it meant that effective fire could be delivered against an accurately located target without ranging. Nevertheless, the mean point of impact was still some tens of yards from the target-centre aiming point. It was not precision fire, but it was good enough for concentrations and barrages. These processes remain in use into the 21st century with refinements to calculations enabled by computers and improved data capture about non-standard conditions. The British Major General Henry Hugh Tudor pioneered armour and artillery cooperation at the breakthrough Battle of Cambrai. The improvements in providing and using data for non-standard conditions (propellant temperature, muzzle velocity, wind, air temperature, and barometric pressure) were developed by the major combatants throughout the war and enabled effective predicted fire. The effectiveness of this was demonstrated by the British in 1917 (at Cambrai) and by Germany the following year (Operation Michael).
Major General J.B.A. Bailey, British Army (retired) wrote: An estimated 75,000 French soldiers were casualties of friendly artillery fire in the four years of World War I. Precision-guidance. Modern artillery is most obviously distinguished by its long range, firing an explosive shell or rocket and a mobile carriage for firing and transport. However, its most important characteristic is the use of indirect fire, whereby the firing equipment is aimed without seeing the target through its sights. Indirect fire emerged at the beginning of the 20th century and was greatly enhanced by the development of predicted fire methods in World War I. However, indirect fire was area fire; it was and is not suitable for destroying point targets; its primary purpose is area suppression. Nevertheless, by the late 1970s precision-guided munitions started to appear, notably the US 155 mm Copperhead and its Soviet 152 mm Krasnopol equivalent that had success in Indian service. These relied on laser designation to 'illuminate' the target that the shell homed onto. However, in the early 21st century, the Global Positioning System (GPS) enabled relatively cheap and accurate guidance for shells and missiles, notably the US 155 mm Excalibur and the 227 mm GMLRS rocket. The introduction of these led to a new issue, the need for very accurate three dimensional target coordinates—the mensuration process.
Weapons covered by the term 'modern artillery' include "cannon" artillery (such as howitzer, mortar, and field gun) and rocket artillery. Certain smaller-caliber mortars are more properly designated small arms rather than artillery, albeit indirect-fire small arms. This term also came to include coastal artillery which traditionally defended coastal areas against seaborne attack and controlled the passage of ships. With the advent of powered flight at the start of the 20th century, artillery also included ground-based anti-aircraft batteries. The term "artillery" has traditionally not been used for projectiles with internal guidance systems, preferring the term "missilery", though some modern artillery units employ surface-to-surface missiles. Advances in terminal guidance systems for small munitions has allowed large-caliber guided projectiles to be developed, blurring this distinction. "See Long Range Precision Fires (LRPF), Joint terminal attack controller" Ammunition. One of the most important roles of logistics is the supply of munitions as a primary type of artillery consumable, their storage (ammunition dump, arsenal, magazine
) and the provision of fuzes, detonators and warheads at the point where artillery troops will assemble the charge, projectile, bomb or shell. A round of artillery ammunition comprises four components: Fuzes. Fuzes are the devices that initiate an artillery projectile, either to detonate its High Explosive (HE) filling or eject its cargo (illuminating flare or smoke canisters being examples). The official military spelling is "fuze". Broadly there are four main types: Most artillery fuzes are nose fuzes. However, base fuzes have been used with armor-piercing shells and for squash head (High-Explosive Squash Head (HESH) or High Explosive, Plastic (HEP) anti-tank shells). At least one nuclear shell and its non-nuclear spotting version also used a multi-deck mechanical time fuze fitted into its base. Impact fuzes were, and in some armies remain, the standard fuze for HE projectiles. Their default action is normally 'superquick', some have had a 'graze' action which allows them to penetrate light cover and others have 'delay'. Delay fuzes allow the shell to penetrate the ground before exploding. Armor or Concrete-Piercing (AP or CP) fuzes are specially hardened. During World War I and later, ricochet fire with delay or graze fuzed HE shells, fired with a flat angle of descent, was used to achieve airburst.
HE shells can be fitted with other fuzes. Airburst fuzes usually have a combined airburst and impact function. However, until the introduction of proximity fuzes, the airburst function was mostly used with cargo munitions—for example, shrapnel, illumination, and smoke. The larger calibers of anti-aircraft artillery are almost always used airburst. Airburst fuzes have to have the fuze length (running time) set on them. This is done just before firing using either a wrench or a fuze setter pre-set to the required fuze length. Early airburst fuzes used igniferous timers which lasted into the second half of the 20th century. Mechanical time fuzes appeared in the early part of the century. These required a means of powering them. The Thiel mechanism used a spring and escapement (i.e. 'clockwork'), Junghans used centrifugal force and gears, and Dixi used centrifugal force and balls. From about 1980, electronic time fuzes started replacing mechanical ones for use with cargo munitions. Proximity fuzes have been of two types: photo-electric or radar. The former was not very successful and seems only to have been used with British anti-aircraft artillery 'unrotated projectiles' (rockets) in World War II. Radar proximity fuzes were a big improvement over the mechanical (time) fuzes which they replaced. Mechanical time fuzes required an accurate calculation of their running time, which was affected by non-standard conditions. With HE (requiring a burst 20 to above the ground), if this was very slightly wrong the rounds would either hit the ground or burst too high. Accurate running time was less important with cargo munitions that burst much higher.
The first radar proximity fuzes (perhaps originally codenamed 'VT' and later called Variable Time (VT)) were invented by the British and developed by the US and initially used against aircraft in World War II. Their ground use was delayed for fear of the enemy recovering 'blinds' (artillery shells which failed to detonate) and copying the fuze. The first proximity fuzes were designed to detonate about above the ground. These air-bursts are much more lethal against personnel than ground bursts because they deliver a greater proportion of useful fragments and deliver them into terrain where a prone soldier would be protected from ground bursts. However, proximity fuzes can suffer premature detonation because of the moisture in heavy rain clouds. This led to 'Controlled Variable Time' (CVT) after World War II. These fuzes have a mechanical timer that switched on the radar about 5 seconds before expected impact, they also detonated on impact. The proximity fuze emerged on the battlefields of Europe in late December 1944. They have become known as the U.S. Artillery's "Christmas present", and were much appreciated when they arrived during the Battle of the Bulge. They were also used to great effect in anti-aircraft projectiles in the Pacific against "kamikaze" as well as in Britain against V-1 flying bombs.
Electronic multi-function fuzes started to appear around 1980. Using solid-state electronics they were relatively cheap and reliable, and became the standard fitted fuze in operational ammunition stocks in some western armies. The early versions were often limited to proximity airburst, albeit with height of burst options, and impact. Some offered a go/no-go functional test through the fuze setter. Later versions introduced induction fuze setting and testing instead of physically placing a fuze setter on the fuze. The latest, such as Junghan's DM84U provide options giving, superquick, delay, a choice of proximity heights of burst, time and a choice of foliage penetration depths. Projectiles. The projectile is the munition or "bullet" fired downrange. This may be an explosive device. Projectiles have traditionally been classified as "shot" or "shell", the former being solid and the latter having some form of "payload". Shells can be divided into three configurations: bursting, base ejection or nose ejection. The latter is sometimes called the shrapnel configuration. The most modern is base ejection, which was introduced in World War I. Base and nose ejection are almost always used with airburst fuzes. Bursting shells use various types of fuze depending on the nature of the payload and the tactical need at the time.
Payloads have included: Propellant. Most forms of artillery require a propellant to propel the projectile to the target. Propellant is always a low explosive, which means it deflagrates, rather than detonating like high explosives. The shell is accelerated to a high velocity in a very short time by the rapid generation of gas from the burning propellant. This high pressure is achieved by burning the propellant in a contained area, either the chamber of a gun barrel or the combustion chamber of a rocket motor. Until the late 19th century, the only available propellant was black powder. It had many disadvantages as a propellant; it has relatively low power, requiring large amounts of powder to fire projectiles, and created thick clouds of white smoke that would obscure the targets, betray the positions of guns, and make aiming impossible. In 1846, nitrocellulose (also known as guncotton) was discovered, and the high explosive nitroglycerin was discovered at nearly the same time. Nitrocellulose was significantly more powerful than black powder, and was smokeless. Early guncotton was unstable, however, and burned very fast and hot, leading to greatly increased barrel wear. Widespread introduction of smokeless powder would wait until the advent of the double-base powders, which combine nitrocellulose and nitroglycerin to produce powerful, smokeless, stable propellant.
Many other formulations were developed in the following decades, generally trying to find the optimum characteristics of a good artillery propellant – low temperature, high energy, non-corrosive, highly stable, cheap, and easy to manufacture in large quantities. Modern gun propellants are broadly divided into three classes: single-base propellants that are mainly or entirely nitrocellulose based, double-base propellants consisting of a combination of nitrocellulose and nitroglycerin, and triple base composed of a combination of nitrocellulose and nitroglycerin and nitroguanidine. Artillery shells fired from a barrel can be assisted to greater range in three ways: Propelling charges for barrel artillery can be provided either as cartridge bags or in metal cartridge cases. Generally, anti-aircraft artillery and smaller-caliber (up to 3" or 76.2 mm) guns use metal cartridge cases that include the round and propellant, similar to a modern rifle cartridge. This simplifies loading and is necessary for very high rates of fire. Bagged propellant allows the amount of powder to be raised or lowered, depending on the range to the target. It also makes handling of larger shells easier. Cases and bags require totally different types of breech. A metal case holds an integral primer to initiate the propellant and provides the gas seal to prevent the gases leaking out of the breech; this is called obturation. With bagged charges, the breech itself provides obturation and holds the primer. In either case, the primer is usually percussion, but electrical is also used, and laser ignition is emerging. Modern 155 mm guns have a primer magazine fitted to their breech.
Artillery ammunition has four classifications according to use: Field artillery system. Because modern field artillery mostly uses indirect fire, the guns have to be part of a system that enables them to attack targets invisible to them, in accordance with the combined arms plan. The main functions in the field artillery system are: All these calculations to produce a quadrant elevation (or range) and azimuth were done manually using instruments, tabulated, data of the moment, and approximations until battlefield computers started appearing in the 1960s and 1970s. While some early calculators copied the manual method (typically substituting polynomials for tabulated data), computers use a different approach. They simulate a shell's trajectory by 'flying' it in short steps and applying data about the conditions affecting the trajectory at each step. This simulation is repeated until it produces a quadrant elevation and azimuth that lands the shell within the required 'closing' distance of the target coordinates.
NATO has a standard ballistic model for computer calculations and has expanded the scope of this into the NATO Armaments Ballistic Kernel (NABK) within the SG2 Shareable (Fire Control) Software Suite (S4). Logistics. Supply of artillery ammunition has always been a major component of military logistics. Up until World War I some armies made artillery responsible for all forward ammunition supply because the load of small arms ammunition was trivial compared to artillery. Different armies use different approaches to ammunition supply, which can vary with the nature of operations. Differences include where the logistic service transfers artillery ammunition to artillery, the amount of ammunition carried in units and extent to which stocks are held at unit or battery level. A key difference is whether supply is 'push' or 'pull'. In the former the 'pipeline' keeps pushing ammunition into formations or units at a defined rate. In the latter units fire as tactically necessary and replenish to maintain or reach their authorised holding (which can vary), so the logistic system has to be able to cope with surge and slack.
Classification. Artillery types can be categorised in several ways, for example by type or size of weapon or ordnance, by role or by organizational arrangements. Types of ordnance. The types of cannon artillery are generally distinguished by the velocity at which they fire projectiles. Types of artillery: Modern field artillery can also be split into two other subcategories: towed and self-propelled. As the name suggests, towed artillery has a prime mover, usually an artillery tractor or truck, to move the piece, crew, and ammunition around. Towed artillery is in some cases equipped with an APU for small displacements. Self-propelled artillery is permanently mounted on a carriage or vehicle with room for the crew and ammunition and is thus capable of moving quickly from one firing position to another, both to support the fluid nature of modern combat and to avoid counter-battery fire. It includes mortar carrier vehicles, many of which allow the mortar to be removed from the vehicle and be used dismounted, potentially in terrain in which the vehicle cannot navigate, or in order to avoid detection.
Organizational types. At the beginning of the modern artillery period, the late 19th century, many armies had three main types of artillery, in some case they were sub-branches within the artillery branch in others they were separate branches or corps. There were also other types excluding the armament fitted to warships: After World War I many nations merged these different artillery branches, in some cases keeping some as sub-branches. Naval artillery disappeared apart from that belonging to marines. However, two new branches of artillery emerged during that war and its aftermath, both used specialised guns (and a few rockets) and used direct not indirect fire, in the 1950s and 1960s both started to make extensive use of missiles: However, the general switch by artillery to indirect fire before and during World War I led to a reaction in some armies. The result was accompanying or infantry guns. These were usually small, short range guns, that could be easily man-handled and used mostly for direct fire but some could use indirect fire. Some were operated by the artillery branch but under command of the supported unit. In World War II they were joined by self-propelled assault guns, although other armies adopted infantry or close support tanks in armoured branch units for the same purpose, subsequently tanks generally took on the accompanying role.
Equipment types. The three main types of artillery "gun" are field guns, howitzers, and mortars. During the 20th century, guns and howitzers have steadily merged in artillery use, making a distinction between the terms somewhat meaningless. By the end of the 20th century, true guns with calibers larger than about 60 mm have become very rare in artillery use, the main users being tanks, ships, and a few residual anti-aircraft and coastal guns. The term "cannon" is a United States generic term that includes guns, howitzers, and mortars; it is not used in other English speaking armies. The traditional definitions differentiated between guns and howitzers in terms of maximum elevation (well less than 45° as opposed to close to or greater than 45°), number of charges (one or more than one charge), and having higher or lower muzzle velocity, sometimes indicated by barrel length. These three criteria give eight possible combinations, of which guns and howitzers are but two. However, modern "howitzers" have higher velocities and longer barrels than the equivalent "guns" of the first half of the 20th century.
True guns are characterized by long range, having a maximum elevation significantly less than 45°, a high muzzle velocity and hence a relatively long barrel, smooth bore (no rifling) and a single charge. The latter often led to fixed ammunition where the projectile is locked to the cartridge case. There is no generally accepted minimum muzzle velocity or barrel length associated with a gun. Howitzers can fire at maximum elevations at least close to 45°; elevations up to about 70° are normal for modern howitzers. Howitzers also have a choice of charges, meaning that the same elevation angle of fire will achieve a different range depending on the charge used. They have rifled bores, lower muzzle velocities and shorter barrels than equivalent guns. All this means they can deliver fire with a steep angle of descent. Because of their multi-charge capability, their ammunition is mostly separate loading (the projectile and propellant are loaded separately). That leaves six combinations of the three criteria, some of which have been termed gun howitzers. A term first used in the 1930s when howitzers with a relatively high maximum muzzle velocities were introduced, it never became widely accepted, most armies electing to widen the definition of "gun" or "howitzer". By the 1960s, most equipment had maximum elevations up to about 70°, were multi-charge, had quite high maximum muzzle velocities and relatively long barrels.
Mortars are simpler. The modern mortar originated in World War I and there were several patterns. After that war, most mortars settled on the Stokes pattern, characterized by a short barrel, smooth bore, low muzzle velocity, elevation angle of firing generally greater than 45°, and a very simple and light mounting using a "baseplate" on the ground. The projectile with its integral propelling charge was dropped down the barrel from the muzzle to hit a fixed firing pin. Since that time, a few mortars have become rifled and adopted breech loading. There are other recognized typifying characteristics for artillery. One such characteristic is the type of obturation used to seal the chamber and prevent gases escaping through the breech. This may use a metal cartridge case that also holds the propelling charge, a configuration called "QF" or "quickfiring" by some nations. The alternative does not use a metal cartridge case, the propellant being merely bagged or in combustible cases with the breech itself providing all the sealing. This is called "BL" or "breech loading" by some nations.
A second characteristic is the form of propulsion. Modern equipment can either be towed or self-propelled (SP). A towed gun fires from the ground and any inherent protection is limited to a gun shield. Towing by horse teams lasted throughout World War II in some armies, but others were fully mechanized with wheeled or tracked gun towing vehicles by the outbreak of that war. The size of a towing vehicle depends on the weight of the equipment and the amount of ammunition it has to carry. A variation of towed is portee, where the vehicle carries the gun which is dismounted for firing. Mortars are often carried this way. A mortar is sometimes carried in an armored vehicle and can either fire from it or be dismounted to fire from the ground. Since the early 1960s it has been possible to carry lighter towed guns and most mortars by helicopter. Even before that, they were parachuted or landed by glider from the time of the first airborne trials in the USSR in the 1930s. In SP equipment, the gun is an integral part of the vehicle that carries it. SPs first appeared during World War I, but did not really develop until World War II. They are mostly tracked vehicles, but wheeled SPs started to appear in the 1970s. Some SPs have no armor and carry few or no other weapons and ammunition. Armored SPs usually carry a useful ammunition load. Early armored SPs were mostly a "casemate" configuration, in essence an open top armored box offering only limited traverse. However, most modern armored SPs have a full enclosed armored turret, usually giving full traverse for the gun. Many SPs cannot fire without deploying stabilizers or spades, sometimes hydraulic. A few SPs are designed so that the recoil forces of the gun are transferred directly onto the ground through a baseplate. A few towed guns have been given limited self-propulsion by means of an auxiliary engine.

Subsets and Splits

No community queries yet

The top public SQL queries from the community will appear here once available.