The basis for the whole modern electric-power industry. Tesla, Nikola (1856-1943) and Henry Harris Lake. A.D 1888, 1st May. [Alternating Current] Complete Specification for Patent No. 6502. Improvements relating to the generation and distribution of electric currents to apparatus therefore. Communicated from abroad by Nikola Tesla, of the city and state of New York, United States of America, electrician. London: Darling & Son for His Majesty's Stationery Office, 1888. 8vo (260 x 185 mm). 1 plate. Disbound. Stitch-holes down the left margin, light toning. FIRST EDITION of the British patent for Tesla's alternating-current polyphase induction motor, which helped usher in the modern age of electricity. This was arguably Tesla's most important patent. The U.S. patent for Tesla's 'electro-magnetic motor' was granted on 1 May 1888, and the British patent-applied for on 1 May 1888-was granted on 1 June. At the time of its introduction Tesla's motor was the only commercially viable electric motor to run on alternating current (AC), the type of electricity favored by Tesla's financial backer, George Westinghouse. Electric motors prior to Tesla's had been designed to run on direct current (DC), the form of electricity favored by Thomas Edison, but AC had a distinct advantage over DC in that it could be transmitted through power lines efficiently at high voltage over longer distances than was possible with DC. The 'war of the currents' between the two competing systems extended into the early 1890s, but Tesla and Westinghouse eventually won the day: 'Although Edison continued to espouse direct current, Tesla's system triumphed to make possible the first large-scale harnessing of Niagara Falls and to provide the basis for the whole modern electric-power industry' (Dictionary of Scientific Biography). V. Smil, 'May 1888: Tesla Files His Patents for the Electric Motor.' IEEE Spectrum, 29 July 2021, spectrum.ieee.org/may-1888-tesla-files-his-patents-for-electric-motor. For further information on this lot please visit Bonhams.com For further information about this lot please visit the lot listing