1844. “Researches on Light and its Chemical Relations,” by Robert Hunt. First edition; second ditto, 1854.
— Robert Hunt recommended proto-sulphate of iron as a developer for Talbot’s calotype negatives; also oxalate of iron and acetate of lead for other purposes.
— A. F. J. Claudet patented a red light for “dark room,” but at that date a red light was not necessary, so the old photographers continued the use of yellow lights.
1845. “Photogenic Manipulations:” Part 1, Calotype, &c.; Part 2, Daguerreotype. By George Thomas Fisher, jun. Published by George Knight and Sons, London.
— “Manual of Photography,” including Daguerreotype, Calotype, &c., by Jabez Hogg. First edition. Second ditto, including Archer’s collodion process, bichloride of mercury bleaching and intensifying, and gutta-percha transfer process, 1856.
1845. “Practical Hints on the Daguerreotype; Willats’s Scientific Manuals.”
— “Plain Directions for Obtaining Photographic Pictures by the Calotype and other processes, on paper; Willats’s Scientific Manuals.” Published by Willats, 98, Cheapside; and Sherwood, Gilbert, and Piper, Paternoster Row.
1846. Gun-cotton made known by Professor Schönbein, of Basel.
1847. Collodion made by dissolving gun-cotton in ether and alcohol, by Mr. Maynard, of Boston, U.S.
1848. “Photogenic Manipulation:” Part II., Daguerreotype, by Robert Bingham. Published by George Knight and Sons, London.