Editing Joseph Priestley (section)

===Educator and historian===
{{further|Joseph Priestley and education}}

All of the books Priestley published while at Warrington emphasised the study of history; Priestley considered it essential for worldly success as well as religious growth. He wrote histories of science and Christianity in an effort to reveal the progress of humanity and, paradoxically, the loss of a pure, "primitive Christianity".<ref>Sheps, 135, 149; Holt, 29–30.</ref>

[[File:A New Chart of History.jpg|thumb|left|alt=A timeline, showing major civilisations|A redacted version of ''[[A New Chart of History]]'' (1765); Priestley believed this chart would "impress" upon students "a just image of the rise, progress, extent, duration, and contemporary state of all the considerable empires that have ever existed in the world"<ref>Qtd. in Sheps, 146.</ref>]]

In his ''[[Essay on a Course of Liberal Education for Civil and Active Life]]'' (1765),<ref>Priestley, Joseph. ''[[Essay on a Course of Liberal Education for Civil and Active Life]]''. London: Printed for C. Henderson under the Royal Exchange; T. Becket and De Hondt in the Strand; and by J. Johnson and Davenport, in Pater-Noster-Row, 1765.</ref> ''[[Lectures on History and General Policy]]'' (1788), and other works, Priestley argued that the education of the young should anticipate their future practical needs. This principle of utility guided his unconventional curricular choices for Warrington's aspiring middle-class students. He recommended modern languages instead of classical languages and modern rather than ancient history. Priestley's lectures on history were particularly revolutionary; he narrated a [[providentialism|providentialist]] and naturalist account of history, arguing that the study of history furthered the comprehension of God's natural laws. Furthermore, his [[millennialism|millennial]] perspective was closely tied to his optimism regarding scientific progress and the improvement of humanity. He believed that each age would improve upon the previous and that the study of history allowed people to perceive and to advance this progress. Since the study of history was a moral imperative for Priestley, he also promoted the education of middle-class women, which was unusual at the time.<ref>Thorpe, 52–54; Schofield (1997), 124–25; Watts, 89, 95–97; Sheps, 136.</ref> Some scholars of education have described Priestley as the most important English writer on education between the 17th-century [[John Locke]] and the 19th-century [[Herbert Spencer]].<ref>Schofield (1997), 121; see also Watts, 92.</ref> ''Lectures on History'' was well received and was employed by many educational institutions, such as New College at Hackney,<!-- Is this [[Homerton College, Cambridge]]? --> [[Brown University|Brown]], [[Princeton University|Princeton]], [[Yale]], and [[University of Cambridge|Cambridge]].<ref>Schofield (2004), 254–59; McLachlan (1987–90), 255–58; Sheps, 138, 141; Kramnick, 12; Holt, 29–33.</ref> Priestley designed two ''Charts'' to serve as visual study aids for his ''Lectures''.<ref>Priestley, Joseph. ''[[A Chart of Biography]]''. London: J. Johnson, St. Paul's Church Yard, 1765 and Joseph Priestley, ''A Description of a Chart of Biography''. Warrington: Printed by William Eyres, 1765 and Joseph Priestley, ''[[A New Chart of History]]''. London: Engraved and published for J. Johnson, 1769; ''A Description of a New Chart of History''. London: Printed for J. Johnson, 1770.</ref> These charts are in fact timelines; they have been described as the most influential timelines published in the 18th century.<ref>Rosenberg, 57–65 and ff.</ref> Both were popular for decades, and the trustees of Warrington were so impressed with Priestley's lectures and charts that they arranged for the [[University of Edinburgh]] to grant him a [[Doctor of Laws|Doctor of Law]] degree in 1764.<ref>Gibbs, 37; Schofield (1997), 118–19.</ref> During this period Priestley also regularly delivered lectures on rhetoric that were later published in 1777 as ''A Course of Lectures on Oratory and Criticism''.<ref>J. Priestley. ''A Course of Lectures on Oratory and Criticism''. London, 1777. Ed. V. M. Bevilacqua & R. Murphy. Carbondale: Southern Illinois University Press, 1965.</ref>

====History of electricity====
[[File:Familiar Introduction to Electricity by Joseph Priestly, plate 7.jpg|thumb|upright|Priestley's "electrical machine for amateur experimentalists", illustrated in the first edition of his ''Familiar Introduction to the Study of Electricity'' (1768)]]<!-- Please don't correct "Priestly" within the filename as this will cause the image to disappear. Thank you. -->

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 Seddon of Warrington|John Seddon]].<ref>Schofield (1997), 136–37; Jackson, 57–61.</ref> Despite Priestley's busy teaching schedule, he decided to write a history of electricity. Friends introduced him to the major experimenters in the field in Britain—[[John Canton]], [[William Watson (scientist)|William Watson]], [[Timothy Lane]], and the visiting [[Benjamin Franklin]] who encouraged Priestley to perform the experiments he wanted to include in his history. Priestley also consulted with Franklin during the latter's kite experiments.<ref>[[#isaacson2004|Isaacson, 2004]], pp. 140–141, 182</ref><ref>[[#vandoren1938|Van Doren]], pp. 164–165</ref> In the process of replicating others' experiments, Priestley became intrigued by unanswered questions and was prompted to undertake experiments of his own design.<ref>Schofield (1997), 141–42, 152; Jackson, 64; Uglow 75–77; Thorpe, 61–65.</ref> (Impressed with his ''Charts'' and the manuscript of his history of electricity, Canton, Franklin, Watson, and [[Richard Price]] nominated Priestley for a fellowship in the [[Royal Society]]; he was accepted in 1766.)<ref>Schofield (1997), 143–44; Jackson, 65–66; see Schofield (1997), 152 and 231–32 for an analysis of the different editions.</ref>
[[File:Priestly-9.jpg|alt=Title page to The History and Present State of Electricity (1769)|thumb|upright|Title page to ''The History and Present State of Electricity'' (1769)]]
In 1767, the 700-page ''[[The History and Present State of Electricity]]'' was published to positive reviews.<ref>Priestley, Joseph. ''[[The History and Present State of Electricity]], with original experiments''. London: Printed for J. Dodsley, J. Johnson and T. Cadell, 1767.</ref> 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. The volume also contains extensive comments on Priestley's views that scientific inquiries be presented with all reasoning in one's discovery path, including false leads and mistakes. He contrasted his narrative approach with Newton's analytical proof-like approach which did not facilitate future researchers to continue the inquiry. Priestley reported some of his own discoveries in the second section, such as the [[Electrical conductivity|conductivity]] of [[charcoal]] and other substances and the continuum between conductors and non-conductors.<ref name=S14456>Schofield (1997), 144–56.</ref> 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.<ref>Schofield (1997), 156–57; Gibbs 28–31; see also Thorpe, 64.</ref> 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]].<ref>Other early investigators who suspected that the electrical force diminished with distance as the gravitational force did (i.e., as the inverse square of the distance) included [[Daniel Bernoulli]] (see: Abel Socin (1760)  ''Acta Helvetia'', vol. 4, pp. 224–25.) and [[Alessandro Volta]], both of whom measured the force between plates of a capacitor, and [[Franz Aepinus|Aepinus]]. See: J.L. Heilbron, ''Electricity in the 17th and 18th Centuries: A Study of Early Modern Physics'' (Los Angeles, California: University of California Press, 1979), pp. 460–62,  [https://books.google.com/books?id=UlTLRUn1sy8C&pg=PA464 464] {{webarchive|url=https://web.archive.org/web/20160514033716/https://books.google.com/books?id=UlTLRUn1sy8C&pg=PA464 |date=14 May 2016 }} (including footnote 44).</ref><ref>Joseph Priestley, ''The History and Present State of Electricity, with Original Experiments'' (London, England: 1767), [https://books.google.com/books?id=HZE_AAAAcAAJ&pg=PA732 p. 732] {{webarchive|url=https://web.archive.org/web/20160528211919/https://books.google.com/books?id=HZE_AAAAcAAJ&pg=PA732 |date=28 May 2016 }}:<br /><blockquote>May we not infer from this experiment, that the attraction of electricity is subject to the same laws with that of gravitation, and is therefore according to the squares of the distances; since it is easily demonstrated, that were the earth in the form of a shell, a body in the inside of it would not be attracted to one side more than another?</blockquote></ref> He did not generalise or elaborate on this,<ref name=S14456/> and the [[Coulomb's law|general law]] was enunciated by French physicist [[Charles-Augustin de Coulomb]] in the 1780s.<ref>Coulomb (1785) [https://books.google.com/books?id=by5EAAAAcAAJ&pg=PA569 "Premier mémoire sur l'électricité et le magnétisme,"] ''Histoire de l'Académie Royale des Sciences'', pp. 569–577</ref>

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).<ref>Priestley, Joseph. ''A Familiar Introduction to the Study of Electricity''. London: Printed for J. Dodsley; T. Cadell; and J. Johnson, 1768.</ref> He marketed the book with his brother Timothy, but unsuccessfully.<ref>Schofield (1997), 228–30.</ref><!--|alt=An illustration of a machine that generated electricity through a wheel and attached to the side of a table.-->