The next steps in the development of atomic theory were the discovery of mysterious electromagnetic waves that could not be seen with the naked eye and an eventual realization that all these waves, regardless of the means used to produce them, were of similar character and were the result of activity within the atom.

The investigation of electromagnetic waves started appropriately, with theoretical predictions of their existence. The first suggestion of electro­magnetic radiation was from an English chemist and physicist named Michael Faraday (1791-1867), who in 1831 started experimenting with elec­tromagnets. Faraday found that a changing magnetic field produces an electric field, and that he could induce electricity in a nearby magnetic coil using a changing magnetic field. Faraday went so far as to propose that electromagnetic forces extended into the empty space surrounding one of his electromagnets, but the idea was roundly rejected by his fellow scientists.