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Fluid theories of electricity are outdated theories that postulated one or more electrical fluids which were thought to be responsible for many electrical phenomena in the history of electromagnetism. The "two-fluid" theory of electricity, created by Charles François de Cisternay du Fay, postulated that electricity was the interaction between two electrical 'fluids.' An alternate simpler theory was proposed by Benjamin Franklin, called the unitary, or one-fluid, theory of electricity. This theory claimed that electricity was really one fluid, which could be present in excess, or absent from a body, thus explaining its electrical charge. Franklin's theory explained how charges could be dispelled and how they could be passed through a chain of people. The fluid theories of electricity eventually became updated to include the effects of magnetism, and electrons.
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Field theory had its origins in the 18th century in a mathematical formulation of Newtonian mechanics, but it was seen as deficient as it implied action at a distance. In 1852, Michael Faraday treated the magnetic field as a physical object, reasoning about lines of force. James Clerk Maxwell used Faraday's conceptualisation to help formulate his unification of electricity and magnetism in his electromagnetic theory.
References
- ↑ Textbook of Human Physiology, Leonard Landois , William Stirling, 1889
- ↑ Scientific Realism: How Science Tracks Truth, Stathis Psillos, 1999, Routledge
- ↑ Jenkin, Fleeming (1868). "The Atomic Theory of Lucretius". The North British Review. 48: 239. Retrieved 30 May 2014.
- ↑ Time of describing a given space from rest under the action of a force varying as the distance from a fixed point. Principia By Sir Isaac Newton. Pg., 86
- ↑ As defined by Boscovich and the French School, an atom was no longer a substantial entity, but a mathematical point, a center of force, and "matter" is a crowd of such points, endowed with inertia and powers of attraction and repulsion.(The Monist: Volume 20. By Edward C. Hegeler, Paul Carus, Hegeler Institute, 1910. Page 220.)
- ↑ The North British review. (1868). Edinburgh: W.P. Kennedy Pg 126.
- ↑ J Lardner, D. (1853 ). A hand-book of mechanics. Philadelphia 223.
- ↑ U.S. patent 60986, Improved imponderable fluid, and mode of generating the same. Jan 1, 1867.
- ↑ Haydn, J., & In Vincent, B. (1893). Haydn's dictionary of dates and universal information relating to all ages and nations. N.Y: G.P. Putnam Pg 28