Electromagnetic Quotes (2 quotes)
The velocity of light is one of the most important of the fundamental constants of Nature. Its measurement by Foucault and Fizeau gave as the result a speed greater in air than in water, thus deciding in favor of the undulatory and against the corpuscular theory. Again, the comparison of the electrostatic and the electromagnetic units gives as an experimental result a value remarkably close to the velocity of lighta result which justified Maxwell in concluding that light is the propagation of an electromagnetic disturbance. Finally, the principle of relativity gives the velocity of light a still greater importance, since one of its fundamental postulates is the constancy of this velocity under all possible conditions.
The word electromagnetic which is used to characterize the phenomena produced by the conducting wires of the voltaic pile, were those which M. Oersted discovered, exhibited by an electric current and a magnet. I have determined to use the word electrodynamic in order to unite under a common name all these phenomena, and particularly to designate those which I have observed between two voltaic conductors. It expresses their true character, that of being produced by electricity in motion: while the electric attractions and repulsions, which have been known for a long time, are electrostatic phenomena produced by the unequal distribution of electricity at rest in the bodies in which they are observed.