Gramophone: specification forming part of Letters Patent No. 372,786, dated 1887 November 8

Diagram and specifications.
Original application filed May 4, 1887, Serial No. 237,060. Divided and this application filed September 26, 1887. Serial No. 250,721.
Patent detailing Emile Berliner's "useful improvements in Gramophones: instead of moving the recording stylus at right angles to and against the record surface, I cause the same to move under the influence of sound-waves..."