Wireless Telegraphy and Telephony

CHAPTER X. REMARKS. ACCOMPLISHMENTS. MAXWELl/S THEORY. hertz's DISCOVERY. THE FUTURE. The history of wireless telegraphy and telephony is a striking- example of how it is possible for scientists laboring in the field of pure research and stimulated by accumulated knowledge and imagination to arrive at discoveries of the most vital importance. Heinrich Hertz and Clerk Maxwell in experimental effort to attain other results unwittingly laid the foundation of this art. In 1867 Maxwell proposed the theory that light is not mere mechanical motion of the ether, but consists of elec- trical undulations. These undulations are partly magnetic and partly electrical. Moreover, according to the theory, the phenomena of electromagnetism and also that of light are due to certain modes of motion in the ether, electric currents, and magnetism, being due to whirls, or body dis- placements in the substance of the ether, while light is due to vibrations to and fro. Twenty years later Hertz discovered the most convincing •experimental proofs of Maxwell’s wonderful theory, and succeeded in producing electromagnetic waves in such a manner that their propagation through space could be examined, and it readily showed that while they were much longer than the ordinary waves of light, they possessed the same properties, were capable of being reflected, polarized, refracted, etc., and traveled at the same speed. 137