Editing Benjamin Franklin (section)

===Electricity, light ===
[[File:Benjamin West, English (born America) - Benjamin Franklin Drawing Electricity from the Sky - Google Art Project.jpg|thumb|''[[Benjamin Franklin Drawing Electricity from the Sky]]'', a {{Circa|1816}} portrait by [[Benjamin West]] now on display at the [[Philadelphia Museum of Art]]]]

Franklin was, along with his contemporary [[Leonhard Euler]], the only major scientist who supported [[Christiaan Huygens]]'s [[wave theory of light]], which was basically ignored by the rest of the [[scientific community]]. In the 18th century, [[Isaac Newton]]'s [[corpuscular theory of light|corpuscular theory]] was held to be true; it took [[Thomas Young (scientist)|Thomas Young's]] well-known [[Double-slit experiment|slit experiment]] in 1803 to persuade most scientists to believe Huygens's theory.<ref>Jogn Gribbin, "In search of Schrödinger's cat", Black Swan, p. 12.</ref>

Franklin started exploring the phenomenon of electricity in the 1740s, after he met the itinerant lecturer Archibald Spencer, who used [[static electricity]] in his demonstrations.{{sfn|Cohen|1990|pp=40–42}} He proposed that "vitreous" and "resinous" electricity were not different types of "[[Fluid theory of electricity|electrical fluid]]" (as electricity was called then), but the same "fluid" under different pressures. (The same proposal was made independently that same year by [[William Watson (scientist)|William Watson]].) He was the first to label them as [[electric charge|positive and negative]] respectively, which replaced the then current distinction made between  'vitreous' and 'resinous' electricity,<ref>[[H. W. Brands]], ''The First American,'' 2002 p.192</ref><ref>{{cite journal|last=Franklin|first=Benjamin|date=May 25, 1747|title=Letter to Peter Collinson|journal=Franklin Papers|url=http://franklinpapers.org/franklin//framedVolumes.jsp?vol=3&page=126b|access-date=May 1, 2016|archive-url=https://web.archive.org/web/20171020014725/http://franklinpapers.org/franklin//framedVolumes.jsp?vol=3&page=126b|archive-date=October 20, 2017|url-status=dead}}</ref><ref>{{cite book |chapter-url=http://scienceworld.wolfram.com/biography/FranklinBenjamin.html |chapter=Benjamin Franklin (1706–1790)  |first=Eric |last=Weisstein |author-link=Eric W. Weisstein |title=Eric Weisstein's World of Scientific Biography }}</ref> and he was the first to discover the principle of [[charge conservation|conservation of charge]].<ref>{{cite web|url=http://www.physchem.co.za/Static%20Electricity/Charge.htm |title=Conservation of Charge |access-date=February 15, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20080218104547/http://www.physchem.co.za/Static%20Electricity/Charge.htm |archive-date=February 18, 2008}}. Archived February 18, 2008.</ref> In 1748, he constructed a multiple plate [[capacitor]], that he called an "electrical battery" (not a true battery like [[Alessandro Volta|Volta's]] [[Voltaic pile|pile]]) by placing eleven panes of glass sandwiched between lead plates, suspended with silk cords and connected by wires.<ref name="paper1749">{{cite journal|journal=Franklin Papers|last=Franklin|first=Benjamin|date=April 29, 1749|title=Further Experiments and Observations in Electricity|url=https://founders.archives.gov/documents/Franklin/01-03-02-0148|access-date=December 21, 2023}}</ref>

In pursuit of more pragmatic uses for electricity, remarking in spring 1749 that he felt "chagrin'd a little" that his experiments had heretofore resulted in "Nothing in this Way of Use to Mankind," Franklin planned a practical demonstration. He proposed a dinner party where a turkey was to be killed via electric shock and roasted on an electrical spit.<ref name="paper1749"/> After having prepared several turkeys this way, he noted that "the birds kill'd in this manner eat uncommonly tender."<ref>[[H. W. Brands]], ''The First American,'' 2002 p.198</ref><ref>{{cite journal|last=Franklin|first=Benjamin|date=February 4, 1751|title=Letter to Peter Collinson|journal=Franklin Papers}}</ref> Franklin recounted that in the process of one of these experiments, he was shocked by a pair of [[Leyden jar]]s, resulting in numbness in his arms that persisted for one evening, noting "I am Ashamed to have been Guilty of so Notorious a Blunder."<ref>{{cite journal|last=Franklin|first=Benjamin|date=December 25, 1750|title=Letter to John Franklin|journal=Franklin Papers}}</ref>

Franklin briefly investigated [[electrotherapy]], including the use of the [[electric bath (electrotherapy)|electric bath]]. This work led to the field becoming widely known.{{sfn|Schiffer|2003|pp=136–37, 301}} In recognition of his work with electricity, he received the [[Royal Society]]'s [[Copley Medal]] in 1753, and in 1756, he became one of the few 18th-century Americans elected a fellow of the Society. The [[centimetre–gram–second system of units|CGS]] unit of electric charge has been named after him: one ''franklin'' (Fr) is equal to one [[statcoulomb]].

Franklin advised Harvard University in its acquisition of new electrical laboratory apparatus after the complete loss of its original collection, in a fire that destroyed the original [[Harvard Hall]] in 1764. The collection he assembled later became part of the [[Harvard Collection of Historical Scientific Instruments]], now on public display in its [[Harvard Science Center|Science Center]].<ref name="Tomase">{{cite news|last1=Tomase|first1=Jennifer|title='A How-To Guide' explores Ben Franklin's 'can-do' legacy|url=http://news.harvard.edu/gazette/2006/06.01/10-franklin.html|access-date=August 9, 2016|work=Harvard University Gazette|date=June 1, 2006|archive-date=July 25, 2010|archive-url=https://web.archive.org/web/20100725214607/http://www.news.harvard.edu/gazette/2006/06.01/10-franklin.html|url-status=dead}}</ref>

====Kite experiment and lightning rod====
[[File:BEP-JONES-Franklin and Electricity.jpg|thumb|''Franklin and Electricity'', a vignette [[Art and engraving on United States banknotes|engraved]] by the [[Bureau of Engraving and Printing]], {{Circa|1860}}]]
Franklin published a proposal for an experiment to prove that [[lightning]] is electricity by [[Kite experiment|flying a kite in a storm]]. On May 10, 1752, [[Thomas-François Dalibard]] of France conducted Franklin's experiment using a {{convert|40|ft|m|adj=mid|-tall}} iron rod instead of a kite, and he extracted electrical sparks from a cloud. On June 15, 1752, Franklin may possibly have conducted his well-known kite experiment in Philadelphia, successfully extracting sparks from a cloud. He described the experiment in his newspaper, ''[[The Pennsylvania Gazette]]'', on October 19, 1752,<ref>Benjamin Franklin, [http://franklinpapers.org/franklin/framedVolumes.jsp?vol=4&page=360a "The Kite Experiment"] {{Webarchive|url=https://web.archive.org/web/20100922095736/http://franklinpapers.org/franklin/framedVolumes.jsp?vol=4&page=360a |date=September 22, 2010 }}, printed in ''[[The Pennsylvania Gazette]]'', October 19, 1752. In The Papers of Benjamin Franklin, The American Philosophical Society and Yale University; digital edition by The Packard Humanities Institute, Vol. 4, p. 360a. Retrieved February 6, 2017.</ref><ref>{{Cite web|title=Pennsylvania Gazette – Benjamin Franklin Historical Society|url=http://www.benjamin-franklin-history.org/pennsylvania-gazette/|access-date=December 30, 2022|language=en-US}}</ref> without mentioning that he himself had performed it.<ref>Steven Johnson (2008) ''The Invention of Air'', p. 39 {{ISBN|978-1-59448-401-8}}. Retrieved February 6, 2017.</ref> This account was read to the Royal Society on December 21 and printed as such in the ''Philosophical Transactions''.<ref name="archives">{{Cite web|title=Founders Online: The Kite Experiment, 19 October 1752|url=http://founders.archives.gov/documents/Franklin/01-04-02-0135|access-date=December 30, 2022|website=founders.archives.gov|language=en}}</ref> [[Joseph Priestley]] published an account with additional details in his 1767 ''History and Present Status of Electricity''. Franklin was careful to stand on an insulator, keeping dry under a roof to avoid the danger of [[Electrical injury|electric shock]].{{sfn|Van Doren|1945|p=159}} Others, such as [[Georg Wilhelm Richmann]] in Russia, were indeed electrocuted in performing lightning experiments during the months immediately following his experiment.<ref>{{cite book|last=Clarke|first=Ronald W.|url=https://archive.org/details/benjaminfranklin00clar_0/page/87|title=Benjamin Franklin, A Biography|publisher=Random House|year=1983|isbn=978-1-84212-272-3|page=[https://archive.org/details/benjaminfranklin00clar_0/page/87 87]|author-link=Ronald W. Clark|url-access=registration}}</ref>

In his writings, Franklin indicates that he was aware of the dangers and offered alternative ways to demonstrate that lightning was electrical, as shown by his use of the concept of [[ground (electricity)|electrical ground]]. He did not perform this experiment in the way that is often pictured in popular literature, flying the kite and waiting to be struck by lightning, as it would have been dangerous.<ref>{{cite web |url=http://www.mos.org/sln/toe/kite.html |title=Franklin's Kite |publisher=[[Museum of Science (Boston)]] |access-date=September 28, 2003 |archive-date=February 9, 2010 |archive-url=https://web.archive.org/web/20100209131349/http://www.mos.org/sln/toe/kite.html |url-status=dead }}</ref> Instead he used the kite to collect some electric charge from a storm cloud, showing that lightning was electrical.<ref name="Wolf"/> On October 19, 1752, in a letter to England with directions for repeating the experiment, he wrote:

{{blockquote|When rain has wet the kite twine so that it can conduct the electric fire freely, you will find it streams out plentifully from the key at the approach of your knuckle, and with this key a phial, or Leyden jar, may be charged: and from electric fire thus obtained spirits may be kindled, and all other electric experiments [may be] performed which are usually done by the help of a rubber glass globe or tube; and therefore the sameness of the electrical matter with that of {{sic|light|ening}} completely demonstrated.<ref name="Wolf">{{cite book |last=Wolf |first=Abraham |title=History of Science, Technology, and Philosophy in the Eighteenth Century |publisher=Macmillan |location=New York |year=1939 |page=232}}</ref>}}

Franklin's electrical experiments led to his invention of the [[lightning rod]]. He said that conductors with a sharp<ref>{{cite news |url=https://www.nytimes.com/1983/06/14/science/lightning-rods-franklin-had-it-wrong.html |title=Lightning Rods: Franklin Had It Wrong |access-date=March 16, 2018 |work=[[The New York Times]] |date=June 1, 1983}}</ref> rather than a smooth point could discharge silently and at a far greater distance. He surmised that this could help protect buildings from lightning by attaching "upright Rods of Iron, made sharp as a Needle and gilt to prevent Rusting, and from the Foot of those Rods a Wire down the outside of the Building into the Ground;&nbsp;... Would not these pointed Rods probably draw the Electrical Fire silently out of a Cloud before it came nigh enough to strike, and thereby secure us from that most sudden and terrible Mischief!" Following a series of experiments on Franklin's own house, lightning rods were installed on the Academy of Philadelphia (later the [[University of Pennsylvania]]) and the Pennsylvania State House (later [[Independence Hall]]) in 1752.<ref>{{Cite journal |title=Benjamin Franklin and Lightning Rods |volume=59 |issue=1 |page=42 |last=Krider |first=Philip |journal=Physics Today |date=January 2006|doi=10.1063/1.2180176 |bibcode=2006PhT....59a..42K |s2cid=110623159 |doi-access=free }}</ref>

Though Franklin is famously associated with kites from his lightning experiments, he has also been noted by many for using kites to pull humans and ships across waterways.<ref>{{cite book| url=http://www.gutenberg.org/files/34193/34193-h/34193-h.htm| title= The True Benjamin Franklin| first= Sydney George| last= Fisher| year=1903 |publisher=J.B. Lippincott Company| location=Philadelphia| edition=5|page=19}}</ref> [[George Pocock (inventor)|George Pocock]] in the book ''A Treatise on The Aeropleustic Art, or Navigation in the Air, by means of Kites, or Buoyant Sails''<ref>{{cite book| url=https://archive.org/details/bub_gb_oMo-DVp_ypUC| title= A Treatise on The Aeropleustic Art, or Navigation in the Air, by means of Kites, or Buoyant Sails| first=George| last=Pocock| page=[https://archive.org/details/bub_gb_oMo-DVp_ypUC/page/n16 9]| publisher=Longmans, Brown, and Co.| location=London| year=1851}}</ref> noted being inspired by Benjamin Franklin's traction of his body by kite power across a waterway.