[f. FERRO- + TYPE.]
1. ‘A term applied by Mr. Robert Hunt, the discoverer, to some photographic processes in which the salts of iron are the principal agents’ (Ogilv.).
1844. R. Hunt, in 14th Rep. Brit. Assoc. (1845), II. 36. On the Ferrotype, and the Property of Sulphate of Iron in developing Photographic Images.
1845. Athenæum, 22 Feb., 203/1. The Energiatype, or, as the discoverer now names the process, the Ferrotype, enables us to keep the pictures invisible on the paper for any length of time, yet bring them out in full force in an instant, by washing with a solution of an iron salt.
2. A process by which positive photographs are taken on thin iron plates; a photograph so taken. Also attrib., as ferrotype plate, process.
1879. G. Prescott, Sp. Telephone, 89. The ferrotype plate used by photographers.
1880. Times, 5 Oct., 6/6. Ferrotypes … so called from being done on thin iron instead of glass.
b. = ferrotype plate.
1879. G. Prescott, Sp. Telephone, 274. Two small blocks of wood … one perforated for the mouth-piece and holding a ferrotype.
Hence Ferrotyper, one who takes photographs by the ferrotype process.
