II — Tesla's contribution to high frequency

DURING the early part of the last decade of the 19th century the attention of the whole scientific world was challenged by Nikola Tesla's public demonstrations of the effects of high-frequency alternating currents. It was then very early in the commercial age of electricity. The incandescent light had not yet become commonplace, electric traction was just being introduced, and the controversy over the relative advantages of the a-c and d-c systems was at its height. Tesla's own contribution to this controversy — one destined to be largely influential in the ultimate establishment of the low-frequency a-c system of distribution — was fresh in mind. The scientific world, stimulated by the brilliant investigations of Hertz in the latter part of the previous decade, was just beginning to adjust itself to the actuality of electrical effects at a distance without the use of wires and to the explanation of them as due to electromagnetic radiation. Further, it must be remembered that the beautiful and curious phenomena of conduction through low-pressure gases at that time had neither lost their novelty nor received any convincing explanation.