This file consists of testimony on behalf of Joseph W. Swan in the case of Edison v. Maxim v. Swan, which involved conflicting claims over who invented the incandescent lamp. The litigants were Edison; Hiram S. Maxim (1840-1916), former chief engineer of the United States Electric Lighting Co. who had emigrated to Great Britain in 1882; and British inventor Joseph W. Swan (1828-1914). Testifying on behalf of Swan were former Menlo Park employees Samuel D. Mott (1852-1930), his brother Charles P. Mott (d. 1908), and Albert B. Herrick (1860-1938). The testimony in the Patent Office file is handwritten, and Herrick's testimony is incomplete.
Samuel Mott entered Edison's employ in September 1879 and assisted in the preparation of many of his patent drawings. In 1881 he was transferred to the Fifth Avenue office of the Edison Electric Light Co. in New York City. He left Edison's employ in June 1882 and subsequently worked for Stephen D. Field, Edward A. Callahan, the Western Electric Co., and the Pope Manufacturing Co. An inventor in his own right, he received thirty-six patents for inventions ranging from an electric cigar lighter to aeronautical devices. Charles Mott worked as an assistant to Edison's personal secretary, Stockton L. Griffin, and Griffin's successor, Samuel Insull. Herrick worked at the Menlo Park laboratory from 1879 until 1881. He was chief electrician for Bergmann & Co. and its successor company, Edison General Electric, from 1886 until 1892.
Related interference records can be found in the Litigation Series in Thomas A. Edison Papers, Part II (1879-1886). Courtesy of the National Archives.