A series of 1919 of photographs of Moorhead Laboratories, San Francisco, reveals the working world of those in the business of producing vacuum tubes. Here men and women work in the Glass Department. Otis Moorhead, a San Francisco native, had worked as a Marconi radio inspector, and had helped Lee de Forest sell his audions at the 1915 Panama Pacific Exposition. Moorhead recognized the possibilities of bootlegging the de Forest tube, and after a brief partnership with fellow counterfeiter Elmer Cunningham, started his own business in 1916. By 1919, Moorhead's company claimed to be the world's largest exclusive electron tube manufacturer. Their products (tubes and other components) were made largely for amateur radio operators, and thus included the offer of "novel wiring diagrams supplied with tubes." The Perham Collection also includes advertising and other printed Moorhead materials.