[3] A lecture delivered before the Franklin Institute, Philadelphia, February, 1893, and before the National Electric Light Association, St. Louis, March, 1893.
[4] See pages 153-4 5.
[5] It is thought necessary to remark that, although the induction coil may give quite a good result when operated with such rapidly alternating currents, yet its construction, quite irrespective of the iron core, makes it very unfit for such high frequencies, and to obtain the best results the construction should be greatly modified.
[6] Article by Mr. Tesla in The Electrical Engineer, N. Y., May 6, 1891.
[7] Article by Mr. Tesla in The Electrical Engineer of Dec. 23d, 1891.
[8] Article by Mr. Tesla in The Electrical Engineer. N. Y., July 1, 1891.
[9] Abstract of a paper read before Physical Society of London.
[9] Article by Mr. Tesla in The Electrical Engineer, N. Y., August 26, 1891.
[10] Note by Prof. J. J. Thomson in the London Electrician, July 24, 1891.
[11] Mr. Tesla's experiments, as the careful reader of his three lectures will perceive, have revealed a very important fact which is taken advantage of in this invention. Namely, he has shown that in a condenser a considerable amount of energy may be wasted, and the condenser may break down merely because gaseous matter is present between the surfaces. A number of experiments are described in the lectures, which bring out this fact forcibly and serve as a guide in the operation of high tension apparatus. But besides bearing upon this point, these experiments also throw a light upon investigations of a purely scientific nature and explain now the lack of harmony among the observations of various investigators. Mr. Tesla shows that in a fluid such as oil the losses are very small as compared with those incurred in a gas.