when tested with powdered lampblack, plumbago, or other pigment in fine powder, and then breathed upon, the color adhered to the hygroscopic portions, forming the shadows, but not to the lights, which had been rendered insoluble by the action of light. After washing in clean water, the print was perfected.
At the same meeting, M. Gabriel de Rumine described a method of obtaining prints analogous in some respects to that of MM. Gamier and Salmon, but rather resembling the patented method of M. Testud de Beauregard. He treated paper with a solution of gelatine and bichromate of potash, and, when dry, covered the surface with black-lead. After exposure under a negative, the print was removed to a dish of boiling water, which removed the soluble portions of the gelatine and the adhering color. M. Brebisson, a few months later, proposed a similar method, applying the color after instead of before exposure.
Mr. Charles Seeley, M.A., editor of the American Journal of Photography, proposed a method with gum, carbon, and a bichromate, mixed, and applied to paper, which he found successful. On learning that M. Poitevin had anticipated this method by several years, he ceased to prosecute it.
In the following year, the Due de Luynes' prize was awarded, an event interesting in the history of carbon printing. In 1856, this nobleman had offered certain prizes for improvements in connection with photography, including one of 2000 francs ($400), for a method of producing permanent prints. A number of processes were forwarded to the Commission, consisting of modifications of silver printing processes; but these were put aside as unsatisfactory, and attention chiefly given to the methods of carbon printing, the competition being
