type of photograph on glass with lights given by silver and shades by a dark background showing through, 1855, American English, apparently from Greek ambrotos "immortal, imperishable" (see ambrosia), with second element from daguerreotype.
This invention consists in an improved process of taking photographic pictures upon glass, and also of beautifying and preserving the same, which process I have styled "ambrotype." My improved process has reference to the art of taking pictures photographically on a film of collodion upon the surface of a sheet of glass, the collodion being suitably prepared for the purpose. By the use of the said process, the beauty and permanency of such pictures are greatly increased, and I have on this account styled the process "ambrotype," from the Greek word ambrotos, immortal. ["Specification of the Patent granted to James A. Cutting, of Boston, in the United States of America, Photographer, for an Improved Process of taking Photographic Pictures upon Glass and also of Beautifying and Preserving the same. Dated London, July 26, 1854," printed in Journal of the Franklin Institute, September 1855]
"of, pertaining to, or resembling in any way Prometheus," 1580s, from Prometheus (q.v.) + -an. Before the introduction of modern matches (see lucifer), promethean was the name given (1830) to small glass tubes full of sulphuric acid, surrounded by an inflammable mixture, which ignited when pressed and afforded a ready light. Related: Prometheans.
Prometheans are small glass bulbs, filled with concentrated sulphuric acid, and hermetically sealed, and surrounded with a mixture of inflammable materials, amongst which the chlorate of potash forms one ; and the whole being again inclosed or surrounded with paper, also rendered still more inflammable by means of resinous matters. Upon pinching the end containing the glass bulb, between the jaws of a pair of pliers, the bulb breaks, and the sulphuric acid instantly kindles the surrounding materials. ["Arcana of Science and Art," London, 1830]
"powdered glass or crystal," by 1904, from French diamanté, past participle of diamanter "to set with diamonds," from Old French diamant (see diamond). Diamante also was a Middle English form of diamond.