[Technology] Partially-Printed Patent for a Precursor of the Television

Washington, D.C.: The United States Patent Office, March 30, 1880. Single sheet, 11 7/8 x 7 3/4 in. (302 x 197 mm). Partially-printed document, being a one-year patent caveat issued to George R. Carey, relating to an improvement in "Electrical Fac-simile Transfer Instruments"; signed in print by Commissioner of Patents H.E. Paine; red paper seal in lower left. Creasing from old folds; offsetting from seal from when folded. Lot includes two engraved diagrams depicting Carey's selenium camera.

In the May 17, 1878 issue of Scientific American, it was reported that, "some very ingenious and curious applications of selenium, in which its peculiar property of changing its electrical conductivity when exposed to light varying in intensity is utilized. The several devices are the invention of Mr. George R. Carey..." Carey (1851–1906), a city surveyor for Boston, based his work on the 1873 research of electrical engineer Willoughby Smith. Smith had discovered selenium's photoconductive properties and, by 1875, had developed a rudimentary method for transmitting images.

In early June 1880 (two months following the issue of this preliminary patent) Scientific American further reported on Carey's "wonderful instruments", publishing illustrations of his devices (see the two included diagrams) and explaining their components and function, describing them as "instruments for transmitting and recording at long distances, permanently or otherwise, by means of electricity, the picture of any object that may be projected by the lens of a camera...The operation of this device depends upon the changes in electrical conductivity produced by the action of light in the metalloid selenium..." (June 5, 1880, Vol. XLII, No. 23, p. 355)

As one of the first proposed systems for pictorial transmission, Carey's device was an early stepping stone towards the development of television, and was influential to the work of scientists such as Constantin Selencq, who invented the first prototype television around the same time. (see Shelton, The Invention of Television, p. 50)

This lot is located in Philadelphia.

[Technology] Partially-Printed Patent for a Precursor of the Television

[Technology] Partially-Printed Patent for a Precursor of the Television