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Elmer Sperry: Electric Searchlight, 1920

Return of the (Scientific) Soldier

An arc light is a type of lamp that produces light when electric current flows across a gap between two electrodes. Sperry applied this principle in developing his own arc light, which he designed and built under the auspices of the Cortland Wagon Company, from 1880 until 1881. With the support of both the wagon company's funds and its engineers, Sperry developed a complete arc light system between the summer of 1880 and the fall of 1882. His work would veer away from electricity in the ensuing years, but Sperry returned to the field in 1914, as the American nation stood on the verge of war.

The U.S. Navy saw a need for a high-intensity searchlight in the early 20th Century, recognizing that the range of existing searchlights was exceeded by that of improved guns. Desirous of eliminating this discrepancy, the navy became interested in the high-intensity searchlight developed by Heinrich Beck. At the time, Beck held the position of manager of the Physikalisch-technisches Laboratorium in Germany. Beck's searchlight boasted a more concentrated beam, and an illuminative capacity five times the standard navy searchlight. Impressed by the reputation of Beck's searchlight, the navy asked the German inventor to estimate the cost of converting existing lights to his design, and of installing new searchlights aboard naval ships. Beck would need to find American manufacturing facilities before he could consider the possibility of undertaking this task, and so Sperry's name was brought into the picture. Beck asked $100,000 for the patent rights to American manufacture and sale.