Wheatstone’s stage fright
Stories from Physics for 11-14 14-16
One of the first public remarks on the electromagnetic nature of light occurred partly by accident. In 1846, Charles Wheatstone (who invented the concertina, stereoscope and, of course, the Wheatstone Bridge) had been due to deliver a lecture at the Royal Society but allegedly panicked and fled before the talk. Faraday stepped in to take his place and improvised a lecture but, lacking enough material to fill the time, he introduced some speculations to the audience. He hypothesised that all of space was permeated by electric and magnetic field lines which, when disturbed, vibrated and that light was a manifestation of such vibrations. Maxwell reported that Faraday’s conjectures, to some extent, prefigured his own electromagnetic theory.