JOSEPH PRIESTLY ,
INVENTER OF SODA WATER , OPTICS , OXYGEN
DIED ON 1804 FEBRUARY 6
Joseph Priestley FRS (/ˈpriːstli/;[2] 24 March [O.S. 13 March] 1733 – 6 February 1804) was an 18th-century English Separatist theologian, natural philosopher, chemist, innovative grammarian, multi-subject educator, and liberal political theorist who published over 150 works. He has historically been credited with the discovery of oxygen,[3] having isolated it in its gaseous state, although Carl Wilhelm Scheele and Antoine Lavoisier also have strong claims to the discovery.[4]
During his lifetime, Priestley's considerable scientific reputation rested on his invention of soda water, his writings on electricity, and his discovery of several "airs" (gases), the most famous being what Priestley dubbed "dephlogisticated air" (oxygen). However, Priestley's determination to defend phlogiston theory and to reject what would become the chemical revolution eventually left him isolated within the scientific community.
Priestley's science was integral to his theology, and he consistently tried to fuse Enlightenment rationalism with Christian theism.[5] In his metaphysical texts, Priestley attempted to combine theism, materialism, and determinism, a project that has been called "audacious and original".[6] He believed that a proper understanding of the natural world would promote human progress and eventually bring about the Christian Millennium.[6] Priestley, who strongly believed in the free and open exchange of ideas, advocated toleration and equal rights for religious Dissenters, which also led him to help found Unitarianism in England. The controversial nature of Priestley's publications, combined with his outspoken support of the French Revolution, aroused public and governmental suspicion; he was eventually forced to flee in 1791, first to London and then to the United States, after a mob burned down his Birmingham home and church. He spent his last ten years in Northumberland County, Pennsylvania.
Early life and education (1733–55)[edit source]
Black-and-white drawing of a two-story brick house along a road.
Priestley's birthplace (since demolished) in Fieldhead, Birstall, West Yorkshire – about six miles (10 km) southwest of Leeds[7]
Priestley was born to an established English Dissenting family (i.e. they did not conform to the Church of England) in Birstall, near Batley in the West Riding of Yorkshire. He was the oldest of six children born to Mary Swift and Jonas Priestley, a finisher of cloth. To ease his mother's burdens, Priestley was sent to live with his grandfather around the age of one. He returned home, five years later, after his mother died. When his father remarried in 1741, Priestley went to live with his aunt and uncle, the wealthy and childless Sarah and John Keighley, 3 miles (4.8 km) from Fieldhead.[8] Because Priestley was precocious—at the age of four he could flawlessly recite all 107 questions and answers of the Westminster Shorter Catechism—his aunt sought the best education for the boy, intending him for the ministry. During his youth, Priestley attended local schools where he learned Greek, Latin, and Hebrew.[9]
Around 1749, Priestley became seriously ill and believed he was dying. Raised as a devout Calvinist, he believed a conversion experience was necessary for salvation, but doubted he had had one. This emotional distress eventually led him to question his theological upbringing, causing him to reject election and to accept universal salvation. As a result, the elders of his home church, the Independent Upper Chapel of Heckmondwike, refused him admission as a full member.[8][10]
Priestley's illness left him with a permanent stutter and he gave up any thoughts of entering the ministry at that time. In preparation for joining a relative in trade in Lisbon, he studied French, Italian, and German in addition to Aramaic, and Arabic. He was tutored by the Reverend George Haggerstone, who first introduced him to higher mathematics, natural philosophy, logic, and metaphysics through the works of Isaac Watts, Willem 's Gravesande, and John Locke.[11]
History of electricity[edit source]
Priestley's "electrical machine for amateur experimentalists", illustrated in the first edition of his Familiar Introduction to the Study of Electricity (1768)
The intellectually stimulating atmosphere of Warrington, often called the "Athens of the North" (of England) during the 18th century, encouraged Priestley's growing interest in natural philosophy. He gave lectures on anatomy and performed experiments regarding temperature with another tutor at Warrington, his friend John
In 1767, the 700-page The History and Present State of Electricity was published to positive reviews.[35] The first half of the text is a history of the study of electricity to 1766; the second and more influential half is a description of contemporary theories about electricity and suggestions for future research. Priestley reported some of his own discoveries in the second section, such as the conductivity of charcoal and other substances and the continuum between conductors and non-conductors.[36] This discovery overturned what he described as "one of the earliest and universally received maxims of electricity", that only water and metals could conduct electricity. This and other experiments on the electrical properties of materials and on the electrical effects of chemical transformations demonstrated Priestley's early and ongoing interest in the relationship between chemical substances and electricity.[37] Based on experiments with charged spheres, Priestley was among the first to propose that electrical force followed an inverse-square law, similar to Newton's law of universal gravitation.[38][39] However, he did not generalise or elaborate on this,[36] and the general law was enunciated by French physicist Charles-Augustin de Coulomb in the 1780s.
Priestley's strength as a natural philosopher was qualitative rather than quantitative and his observation of "a current of real air" between two electrified points would later interest Michael Faraday and James Clerk Maxwell as they investigated electromagnetism. Priestley's text became the standard history of electricity for over a century; Alessandro Volta (who later invented the battery), William Herschel (who discovered infrared radiation), and Henry Cavendish (who discovered hydrogen) all relied upon it. Priestley wrote a popular version of the History of Electricity for the general public titled A Familiar Introduction to the Study of Electricity (1768).[40] He marketed the book with his brother Timothy, but unsuccessfully.[41]
Natural philosopher: electricity, Optics, and soda water[edit source]
Optics: The History and Present State of Vision, Light, and Colours, published in 1772, London
Although Priestley claimed that natural philosophy was only a hobby, he took it seriously. In his History of Electricity, he described the scientist as promoting the "security and happiness of mankind".[63] Priestley's science was eminently practical and he rarely concerned himself with theoretical questions; his model was Benjamin Franklin. When he moved to Leeds, Priestley continued his electrical and chemical experiments (the latter aided by a steady supply of carbon dioxide from a neighbouring brewery). Between 1767 and 1770, he presented five papers to the Royal Society from these initial experiments; the first four papers explored coronal discharges and other phenomena related to electrical discharge, while the fifth reported on the conductivity of charcoals from different sources. His subsequent experimental work focused on chemistry and pneumatics.[64]
Priestley published the first volume of his projected history of experimental philosophy, The History and Present State of Discoveries Relating to Vision, Light and Colours (referred to as his Optics), in 1772.[65] He paid careful attention to the history of optics and presented excellent explanations of early optics experiments, but his mathematical deficiencies caused him to dismiss several important contemporary theories. Furthermore, he did not include any of the practical sections that had made his History of Electricity so useful to practising natural philosophers. Unlike his History of Electricity, it was not popular and had only one edition, although it was the only English book on the topic for 150 years. The hastily written text sold poorly; the cost of researching, writing, and publishing the Optics convinced Priestley to abandon his history of experimental philosophy.[66]
Priestley was considered for the position of astronomer on James Cook's second voyage to the South Seas, but was not chosen. Still, he contributed in a small way to the voyage: he provided the crew with a method for making soda water, which he erroneously speculated might be a cure for scurvy. He then published a pamphlet with Directions for Impregnating Water with Fixed Air (1772).[67] Priestley did not exploit the commercial potential of soda water, but others such as J. J. Schweppe made fortunes from it.[68] In 1773, the Royal Society recognised Priestley's achievements in natural philosophy by awarding him the Copley Medal.[69]
Priestley's friends wanted to find him a more financially secure position. In 1772, prompted by Richard Price and Benjamin Franklin, Lord Shelburne wrote to Priestley asking him to direct the education of his children and to act as his general assistant. Although Priestley was reluctant to sacrifice his ministry, he accepted the position, resigning from Mill Hill Chapel on 20 December 1772, and preaching his last sermon on 16 May 1773.[70]
Legacy[edit source]
Statue of a man with a mortar and pestle in his left hand and his right hand upraised
Statue of Priestley by Francis John Williamson, in Chamberlain Square, Birmingham, England.
By the time he died in 1804, Priestley had been made a member of every major scientific society in the Western world and he had discovered numerous substances.[180] The 19th-century French naturalist George Cuvier, in his eulogy of Priestley, praised his discoveries while at the same time lamenting his refusal to abandon phlogiston theory, calling him "the father of modern chemistry [who] never acknowledged his daughter".[181] Priestley published more than 150 works on topics ranging from political philosophy to education to theology to natural philosophy.[182] He led and inspired British radicals during the 1790s, paved the way for utilitarianism,[183] and helped found Unitarianism.[184] A wide variety of philosophers, scientists, and poets became associationists as a result of his redaction of David Hartley's Observations on Man, including Erasmus Darwin, Coleridge, William Wordsworth, John Stuart Mill, Alexander Bain, and Herbert Spencer.[185] Immanuel Kant praised Priestley in his Critique of Pure Reason (1781), writing that he "knew how to combine his paradoxical teaching with the interests of religion".[6] Indeed, it was Priestley's aim to "put the most 'advanced' Enlightenment ideas into the service of a rationalized though heterodox Christianity, under the guidance of the basic principles of scientific method".[183]
Considering the extent of Priestley's influence, relatively little scholarship has been devoted to him. In the early 20th century, Priestley was most often described as a conservative and dogmatic scientist who was nevertheless a political and religious reformer.[186] In a historiographic review essay, historian of science Simon Schaffer describes the two dominant portraits of Priestley: the first depicts him as "a playful innocent" who stumbled across his discoveries; the second portrays him as innocent as well as "warped" for not understanding their implications better. Assessing Priestley's works as a whole has been difficult for scholars because of his wide-ranging interests. His scientific discoveries have usually been divorced from his theological and metaphysical publications to make an analysis of his life and writings easier, but this approach has been challenged recently by scholars such as John McEvoy and Robert Schofield. Although early Priestley scholarship claimed that his theological and metaphysical works were "distractions" and "obstacles" to his scientific work, scholarship published in the 1960s, 1970s, and 1980s maintained that Priestley's works constituted a unified theory. However, as Schaffer explains, no convincing synthesis of his work has yet been expounded.[187] More recently, in 2001, historian of science Dan Eshet has argued that efforts to create a "synoptic view" have resulted only in a rationalisation of the contradictions in Priestley's thought, because they have been "organized around philosophical categories" and have "separate[d] the producers of scientific ideas from any social conflict".[188]
A blue plaque from the Royal Society of Chemistry commemorates Priestley at New Meeting Street, Birmingham
Priestley has been remembered by the towns in which he served as a reforming educator and minister and by the scientific organisations he influenced. Two educational institutions have been named in his honour—Priestley College in Warrington and Joseph Priestley College in Leeds[189] (now part of Leeds City College)—and an asteroid, 5577 Priestley, discovered in 1986 by Duncan Waldron.[190] In Birstall, the Leeds City Square, and in Birmingham, he is memorialised through statues,[191] and plaques commemorating him have been posted in Birmingham, Calne and Warrington.[192] Also, since 1952 Dickinson College, Pennsylvania, has presented the Priestley Award to a scientist who makes "discoveries which contribute to the welfare of mankind".[193] The main undergraduate chemistry laboratories at the University of Leeds were refurbished as part of a £4m refurbishment plan in 2006 and renamed as the Priestley Laboratories in his honour as a prominent chemist from Leeds.[194] In 2016 the University of Huddersfield renamed the building housing its Applied Sciences department as the Joseph Priestley Building, as part of an exercise to rename all campus buildings after prominent local figures.[195]
Additional recognition for Priestley's work is marked by a National Historic Chemical Landmark designation for his discovery of oxygen, made on 1 August 1994, at the Priestley House in Northumberland, Penn., by the American Chemical Society. Similar international recognition was made on 7 August 2000, at Bowood House in Wiltshire, UK.[196]
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