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Elmer Sperry: Electric Searchlight, 1920

Seeing the Light

Sperry's own experience working with arc lights convinced him that the Beck design wanted improvement, and he was not under the impression that Beck's patent protected his lamp against imitation or competition. Having encountered resistance from Sperry, Beck sold his patents to General Electric for $135,000, and General Electric in turn supplied the navy with the Beck high-intensity light.

Sperry responded to this business transaction by investing in the development of his own version of the high-intensity lamp. Sperry informed the navy of his plans for improving the Beck searchlight in 1914. The cunning inventor proposed to do away with the alcohol vapor with which Beck surrounded and cooled the arc lamp, to simplify the automatic mechanisms in the searchlight, and to opt for the use of pure carbon electrodes rather than impregnated carbon. Sperry worked closely with a new member of his staff, Preston Bassett, on the development of the searchlight.

A graduate of Amherst and a Chemistry major, Bassett's help proved invaluable. He worked closely with the National Carbon Company in Cleveland to develop improved carbon electrodes for the high-intensity light, and designed a positive electrode that would render the light more powerful. The chemistry and design of the carbons and the positioning of the positive and negative electrodes in Sperry's lamp set his design apart from Beck's. Different, too, was Sperry's method of cooling the electrodes and thus restricting the flow of current in his lamp. Beck used alcohol vapor to accomplish cooling, but Sperry deemed his apparatus for generating the alcohol fumes and directing them to the electrodes clumsy. Sperry and Bassett therefore resorted to air cooling.