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{{wiktionary}}
 
== History ==
[[किपा:Thales.jpg|thumb|right|upright|Thales, the earliest researcher into electricity]]
{{main|History of electromagnetism}}
{{seealso|Etymology of electricity}}
 
Long before any knowledge of electricity existed people were aware of shocks from [[electric fish]]es. [[Ancient Egypt]]ian texts dating from [[2750 BC]] referred to these fish as the "Thunderer of the [[Nile]]", and described them as the "protectors" of all other fish. They were again reported millennia later by [[ancient Greek]], [[Roman Empire|Roman]] and [[Islamic geography|Arabic naturalists]] and [[Islamic medicine|physicians]].<ref>{{citation|title=Review: Electric Fish|first=Peter|last=Moller|journal=BioScience|volume=41|issue=11|date=December 1991|pages=794-6 [794]}}</ref> Several ancient writers, such as [[Pliny the Elder]] and [[Scribonius Largus]], attested to the numbing effect of [[electric shock]]s delivered by [[Electric catfish|catfish]] and [[torpedo ray]]s, and knew that such shocks could travel along conducting objects.<ref name=Electroreception>
{{citation
| first = Theodore H. | last = Bullock
| title = Electroreception
| pages = 5–7
| publisher = Springer
| year = 2005
| isbn = 0387231927}}
</ref> Patients suffering from ailments such as [[gout]] or [[headache]] were directed to touch electric fish in the hope that the powerful jolt might cure them.<ref name=morris>
{{citation
| first = Simon C. | last = Morris
| title = Life's Solution: Inevitable Humans in a Lonely Universe
| pages = 182–185
| publisher = Cambridge University Press
| year = 2003
| isbn = 0521827043}}</ref> Possibly the earliest and nearest approach to the discovery of the identity of [[lightning]], and electricity from any other source, is to be attributed to the [[Physics in medieval Islam|Arabs]], who before the 15th century had the [[Arabic language|Arabic]] word for lightning (''raad'') applied to the [[electric ray]].<ref name="EncyclopediaAmericana">''The [[Encyclopedia Americana]]; a library of universal knowledge'' (1918), [[New York]]: Encyclopedia Americana Corp</ref>
 
That certain objects such as rods of [[amber]] could be rubbed with cat's fur and attract light objects like feathers was known to ancient cultures around the [[Mediterranean Sea|Mediterranean]]. [[Thales of Miletos]] made a series of observations on [[static electricity]] around 600 BC, from which he believed that friction rendered amber [[magnetic]], in contrast to minerals such as [[magnetite]], which needed no rubbing.<ref name=stewart>
{{Citation
| first = Joseph | last= Stewart
| title = Intermediate Electromagnetic Theory
| publisher = World Scientific
| year = 2001
| page = 50
| isbn = 9-8102-4471-1}}
</ref><ref>
{{Citation
| first = Brian | last = Simpson
| title = Electrical Stimulation and the Relief of Pain
| publisher = Elsevier Health Sciences
| year = 2003
| pages = 6–7
| isbn = 0-4445-1258-6}}
</ref> Thales was incorrect in believing the attraction was due to a magnetic effect, but later science would prove a link between magnetism and electricity. According to a controversial theory, the [[Parthia]]ns may have had knowledge of [[electroplating]], based on the 1936 discovery of the [[Baghdad Battery]], which resembles a [[galvanic cell]], though it is uncertain whether the artefact was electrical in nature.<ref>
{{Citation
| first = Arran | last = Frood
| title = Riddle of 'Baghdad's batteries'
| publisher = BBC
| date = [[27 February]] [[2003]]
| accessdate = 2008-02-16
| url = http://news.bbc.co.uk/1/hi/sci/tech/2804257.stm}}
</ref>
[[किपा:Franklin-Benjamin-LOC.jpg|thumb|left|upright|Benjamin Franklin conducted extensive research on electricity in the 18th century]]
 
Electricity would remain little more than an intellectual curiosity for millennia until 1600, when the English physician [[William Gilbert]] made a careful study of electricity and magnetism, distinguishing the [[lodestone]] effect from static electricity produced by rubbing amber.<ref name=stewart/> He coined the [[New Latin]] word ''electricus'' ("of amber" or "like amber", from ''ήλεκτρον'' [''elektron''], the Greek word for "amber") to refer to the property of attracting small objects after being rubbed.<ref>
{{Citation
| first = Brian | last = Baigrie
| title = Electricity and Magnetism: A Historical Perspective
| publisher = Greenwood Press
| year = 2006
| pages = 7–8
| isbn = 0-3133-3358-0}}
</ref> This association gave rise to the English words "electric" and "electricity", which made their first appearance in print in [[Thomas Browne]]'s ''[[Pseudodoxia Epidemica]]'' of 1646.<ref>
{{Citation
| first = Gordon | last = Chalmers
| title = The Lodestone and the Understanding of Matter in Seventeenth Century England
| journal = Philosophy of Science
| year = 1937
| volume = 4
| issue = 1
| pages = 75–95}}</ref>
 
Further work was conducted by [[Otto von Guericke]], [[Robert Boyle]], [[Stephen Gray (scientist)|Stephen Gray]] and [[C. F. du Fay]]. In the 18th century, [[Benjamin Franklin]] conducted extensive research in electricity, selling his possessions to fund his work. In June 1752 he is reputed to have attached a metal key to the bottom of a dampened kite string and flown the kite in a storm-threatened sky.<ref>
{{citation
| first = James | last = Srodes
| title = Franklin: The Essential Founding Father
| pages = 92–94
| year = 2002
| publisher = Regnery Publishing
| isbn = 0895261634}} It is uncertain if Franklin personally carried out this experiment, but it is popularly attributed to him.</ref> He observed a succession of sparks jumping from the key to the back of his hand, showing that [[lightning]] was indeed electrical in nature.<ref>{{cite book
| last = Uman
| first = Martin
| authorlink = Martin A. Uman
| title = All About Lightning
| publisher = Dover Publications
| date = 1987
| url = http://ira.usf.edu/CAM/exhibitions/1998_12_McCollum/supplemental_didactics/23.Uman1.pdf
| isbn = 048625237X}}</ref>
 
In 1791 [[Luigi Galvani]] published his discovery of [[bioelectricity]], demonstrating that electricity was the medium by which [[nerve cell]]s passed signals to the muscles.<ref name=kirby>
{{citation
| first = Richard S. | last = Kirby
| title = Engineering in History
| pages = 331–333
| year = 1990
| publisher = Courier Dover Publications
| isbn = 0486264122}}
</ref> [[Alessandro Volta]]'s battery, or [[voltaic pile]], of 1800, made from alternating layers of zinc and copper, provided scientists with a more reliable source of electrical energy than the [[electrostatic machine]]s previously used.<ref name=kirby/> The recognition of [[electromagnetism]], the unity of electric and magnetic phenomena, is due to [[Hans Christian Ørsted]] and
[[André-Marie Ampère]] in 1819-1820; [[Michael Faraday]] invented the [[electric motor]] in 1821, and [[Georg Ohm]] mathematically analysed the electrical circuit in 1827.<ref name=kirby/>
 
While it had been the early 19th century that had seen rapid progress in electrical science, the late 19th century would see the greatest progress in [[electrical engineering]]. Through such people as [[Nikola Tesla]], [[Thomas Edison]], [[George Westinghouse]], [[Ernst Werner von Siemens]], [[Alexander Graham Bell]] and [[William Thomson, 1st Baron Kelvin|Lord Kelvin]], electricity was turned from a scientific curiosity into an essential tool for modern life, becoming a driving force for the [[Second Industrial Revolution]].<ref>
{{Citation
| first = Dragana | last = Marković
| title = The Second Industrial Revolution
| url= http://www.b92.net/eng/special/tesla/life.php?nav_id=36502
| accessdate = 2007-12-09}}
</ref>{{clear}}
 
== Concepts ==