Nikola Tesla Books
clearly uneconomical, and was discarded. A series of alternate proposals were then received. In 1893, Westinghouse received the initial contract for three 5000 hp Tesla polyphase generators, which were then the largest generators ever designed. The simultaneous development of the Niagara project and the Tesla System was a fortuitous coincidence. No adequate method of handling large power was available in 1890, but the development of the polyphase apparatus justified the decision on May 6, 1893 (5 years and 5 days after the issuing of the Tesla Patents) to use his system. The polyphase system brought success to Niagara, and Niagara bought immediate prestige to the new electric system. Power was delivered in August 1895 to the first customer (Pittsburgh Reduction Company now Alcoa) for producing aluminum by the Hall process. In 1896, the first long distance transmission of polyphase power from Niagara to Buffalo was inaugurated. This was the culmination of a gigantic and universal system capable of uniting many power sources in a superpower system, using the Tesla concept. At the turn of the century, this was described as "the New Epoch" in human progress, probably the most significant event since the invention of the written alphabet marked the step from barbarism to civilization. Morrison described this step in the following words: "The evolution of electric power from the initial research of Faraday in 1831, to the installation of the Tesla System in 1896 is undoubtedly the single most tremendous event in the engineering history of the world." After working with Westinghouse on the development of the induction motor, Tesla returned to New York City (1889) to continue his work. He began his studies of high frequency phenomena which would occupy his attention for the rest of his life. He developed a series of high frequency generators operating at the frequency of 20kHz, using them as a source for radio transmission. The utilization of these generators became very important in 1910, but they were superseded by the troide tube in 1922. In 1887 Hertz had demonstrated the existence of electromagnetic waves predicted by Maxwell many years earlier (1856). Tesla seems to have felt that new mechanisms of transmission would manifest themselves if the power were high enough, and he set about to produce high frequency power on a vast scale. Other experimenters of the time were content to use a few watts of power, and were primarily concerned with communications. Tesla's first contribution to the field of high frequency phenomena was to recognize the importance of the resonance phenomena in AC circuits, later developed and expanded by Charles Steinmetz at General Electric. AC circuits are composed of inductance (such as a coil) and capacitance (condensors), and a particular combination will oscillate at a frequency determined by the product of the two. Two circuits, placed near each other, and designed so that the resonant frequency is the same, are called "tuned circuits." Tesla utilized the principle of tuned circuits in designing a high frequency transformer to produce the high powers he felt necessary for power transmission. He also was clearly the originator of the concept of inductive coupling between tuned circuits. (Incidentally, when you rotate the dial on a radio, what you are doing is tuning the resonant circuit in your radio by varying the capacitance of the circuit, precisely as Tesla said.) He also utilized the concept of a capacitance loaded open secondary circuit (but it is not entirely clear that he realized the effect of antenna capacitance on the tuning of his circuits). As Wheeler states: "It seems incontestible that all three of these fundamental ideas are clearly revealed in Tesla's patent applications and lectures prior to 1894, although the application to communications, while mentioned, is made incidental to power transmission. As none of these ideas appears in the literature prior to the patent specifications of Marconi, Lodge and Braun (1897-1900), it would seem that Tesla's name is worthy of perpetuation as the pioneer of these ideas which are so basic in the field of radio engineering." 19 Thus, he should be considered a pioneer of the fundamental ideas, but not a progenitor of their useful applications, except in that his work was a stimulus to others. In addition, he clearly developed (and patented) the first known application of what we now know as remote radio control (Patent no. 613809, November 8, 1898). During his research on the effects of high frequency fields, Tesla developed many experimental demonstrations of the effect of high frequency discharges in gases. He appears, at this time, to have developed the concept of including a phosphor coating to the inside of a gaseous discharge tube (again energized by a high frequency field, also without wire connections) to produce what we now call fluorescent lighting. In 1895, his laboratory was destroyed by fire, but in 1896 he succeeded in transmitting signals over a distance of 20 miles. In 1899, he established the Colorado Springs Laboratory to investigate his concept of exciting the entire earth into oscillations. It is clear that he utilized the concept of a high aerial and ground connections, but again using very high voltage (of the order of 20-30 million volts). He succeeded in transmitting enough power to light a lamp at a distance of 30 km., and to detect a signal at a distance of about 1000 km. He also "succeeded" in destroying the Colorado Power Company main generator, which abruptly terminated his experiments. He later built a laboratory on Long Island (Shoreham), but the experiments were not completed. At about this time, he began to fall short of funds. O'Neill's biography of Tesla relates the story that the Tesla patents were purchased by Westinghouse for one million dollars plus one dollar per HP royalty. In 1915, when Westinghouse needed expansion funds, Tesla invalidated the agreement, because of the faith in polyphase systems exhibited by Westinghouse. It is interesting to note that the first nuclear reaction induced by accelerators (1933) by Breit, Tuve, Dahl at the University of Wisconsin utilized the Tesla transformer. Perhaps the greatest impact, aside from his actual discoveries, was in the effect his work had on others. The only individual whose ingenuity and breadth of
