The William H. Offenhauser, Jr. papers are composed of notes, schematics, and correspondence from his work at RCA Photophone on recording sound on motion picture film. The papers include licensing agreements, meeting reports on the progress and problems of Photophone technology, parts catalogs, RCA press materials like the booklet, “RCA, who we are and what we do,” and a copy of his patent for “Sound Reproduction” by light (2,018,315). Of special note is a list of movie theaters with sound motion picture projection rooms in New York in 1928.