In papers published in the 1860s, James Clerk Maxwell concisely summarized all the known laws of electricity and magnetism in a set of four equations.1 Through the application of these equations, Maxwell predicted the existence of electromagnetic waves and showed that they travel through space with the speed of light. Not only did Maxwell’s equations provide an elegant way of describing electromagnetic phenomena but, as importantly, they led Maxwell to conclude that light is a form of electromagnetic radiation.
Initially, many in the scientific community were hesitant to accept Maxwell’s theory of electromagnetism. Then, in 1888, German physicist Heinrich Hertz observed that an induction coil-produced spark jumping across a gap between two electrodes produced a weak spark across a similar pair of electrodes several meters away (Fig. 1).2,3 Since there was no physical connection between the two pairs of electrodes, Hertz concluded that he had produced and...
