[D9244AAC], Letter from Iowa Phonograph Co, Whitfield Stinson to Thomas Alva Edison, March 22nd, 1892
https://edisondigital.rutgers.edu/document/D9244AAC
Transcription
[TAE Marginalia] Berhner does this but results are poor Received Mar 25 1892 Ans March 22nd 1892 Thos T.A. Edison Orange, N.J. Dear Sir:- The Exhibition feature now being its chief source of revenue, some suggestions are offered with view of improving records and increasing receipt of Phonograph. For brevities sake I assure that these have been worked out satisfactorily. Make a blank of sensitized glue, coat with photographic film, place it with necessary mechanism within darkened box, have lamp, reflector, lenze, screen &c arranged something like enclosed sketch. This combination produces a sinnous record photographed upon the surface of blank. Wash away superfluous sliver, harden the exposed glue, strip off film and dissolve out the glue protected by photography. This leaves a cam like negative for reduplicating. A lever fixed with reproducing and recording points, the ne to follow the cam, the other to make the copy, completes the work. By running speed very low-say ten revolutions, indestructible metal records are made for dolls &c. This scheme cuts vibrations in their full amplitude into the ordinary blank, permits use of the most delicate diaphragm, avoids dreadful jarring sounds heard in loud records made with diaphragm and point in contact with blank. It makes piano and vocal soprano records and records of the largest band and chorus by enabling the machine to stand far enough away to take in sounds from extreme ends of stage. Also delicate lung and heart records for use of physicians. So small percentage and heart records as now made are at once pleasingly soft and sufficiently loud and this more tedious process proves vastly profitable. Very truly yours, Whitfield Stinson Party