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<Michael Faraday> established new electrical phenomena through carefully varied experiments and made the field a central explanatory concept. His achievements were not confined to a single apparatus or to applications later expressed in equations by other researchers.
In 1821 he demonstrated continuous electromagnetic <rotation>: a current-carrying conductor could move around a magnet, or a magnet around a conductor, with the current maintained through an appropriate contact. The circular motion was difficult to reduce to an ordinary static attraction along a line and provided an experimental route toward electric-motor action.
In 1831 his induction experiments linked changing magnetic conditions to an induced electrical response. In the ring-coil arrangement, switching current in one winding produced a transient deflection in the other winding rather than a persistent response to a steady current. Moving a magnet relative to a coil produced a related effect. Comparing these arrangements helped identify change of magnetic linkage, rather than mere proximity to a magnet, as the essential feature. His rotating-disc generator showed a further way to obtain electrical output from mechanical motion.<Michael Faraday's ring-coil apparatus by Royal Institution>[two windings and transient induction response]{ref}
His <electrolysis> studies established quantitative relationships between charge transferred and material deposited or liberated. These supported a connection between chemical change and definite electrical quantities, even though they did not yet amount to a modern atomic theory of charge. His work on dielectrics and <electrostatic shielding> examined how materials and conducting boundaries influence electrical effects.
In 1845 he observed magnetic <rotation> of the plane of polarization in a material and investigated <diamagnetism>. The magneto-optical effect gave experimental evidence for a connection between light and magnetism, while <diamagnetism> showed a response opposite to ordinary magnetic attraction. Those findings broadened electromagnetism beyond currents and permanent magnets.<Michael Faraday (1791–1867)>[chronology of <rotations>, induction, <electrolysis> and the 1845 discoveries]{ref}
Faraday's lines of <force> emphasized processes in the intervening region rather than only direct action at a distance. <James Clerk Maxwell> subsequently converted crucial parts of that field conception into a mathematical electromagnetic theory. Calling Faraday merely an unmathematical precursor would miss the explanatory and experimental content of his field ideas; crediting him with Maxwell's completed equations would be equally inaccurate. His legacy combines new effects, reproducible experimental techniques, quantitative electrochemistry and a fertile physical picture of fields.
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