Nikola Tesla (1856-1943) was a Serbian-American electrical inventor, whose main claim to fame lay with his invention of the alternating current motor. He had 700 patents in the US and Europe and his discoveries include the Tesla Coil, fluorescent light, wireless transmission of electrical energy, radio, remote control, discovery of cosmic radio waves and use of ionosphere for scientific purposes.
Tesla was from a family of Serbian origin and training for an engineering career, he attended the Technical University at Graz, Austria, and the University of Prague. At Graz he first saw the Gramme dynamo, which operated as a generator and, when reversed, became an electric motor, and he conceived a way to use alternating current to advantage. Later, at Budapest, he visualized the principle of the rotating magnetic field and developed plans for an induction motor that would become his first step toward the successful utilization of alternating current. In 1882 Tesla went to work in Paris for the Continental Edison Company, and, while on assignment to Strassburg in 1883, he constructed, in after-work hours, his first induction motor.
Tesla sailed for New York in 1884, and in May 1885, George Westinghouse, head of the Westinghouse Electric Company in Pittsburgh, bought the patent rights to Tesla's polyphase system of alternating-current dynamos, transformers, and motors. He soon established his own laboratory, where he experimented with shadowgraphs similar to those that later were to be used by Wilhelm Röntgen when he discovered X-rays in 1895. Tesla gave exhibitions in his laboratory in which he lighted lamps without wires by allowing electricity to flow through his body. The Tesla coil, which he invented in 1891, is widely used today in radio and television sets and other electronic equipment.
Westinghouse used Tesla's system to light the World's Columbian Exposition at Chicago in 1893. His success was a factor in winning him the contract to install the first power machinery at Niagara Falls. In 1898 Tesla announced his invention of a teleautomatic boat guided by remote control. When skepticism was voiced, Tesla proved his claims for it before a crowd in Madison Square Garden.
In Colorado Springs, where he stayed from May 1899 until early 1900, Tesla made what he regarded as his most important discovery - terrestrial stationary waves. He also lighted 200 lamps without wires from a distance of 25 miles (40 kilometres). Returning to New York in 1900, Tesla began construction on Long Island of a wireless world broadcasting tower, with $150,000 capital from the American financier J. Pierpont Morgan. He expected to provide worldwide communication and to furnish facilities for sending pictures, messages, weather warnings, and stock reports. The project was abandoned because of a financial panic, labour troubles, and Morgan's withdrawal of support.
Tesla's work then shifted to turbines and other projects. Because of a lack of funds, his ideas remained in his notebooks, which are still examined by engineers for unexploited clues.