GRAPHY.
There have been many other processes suggested for securing photographs in colours, most of which were simply fore runners or variations of those already dealt with, and are by this time practically forgotten. In 1897 much excitement was caused in the photographic world by a process introduced by MM. Dansae and Chassagne, two French scientists, in which it was claimed that certain coloured solu tions brushed in turn over a transparency or print, treated in a special manner, adhered selectively to their own proper portions of the picture, giving a correct reproduction of the original. This preten sion, however, was not considered to be substantiated, it being generally agreed that the process resolved itself simply into a method of tinting prints with aniline dyes. In 1809, Mr. Wallace Bennetto, of New quay, introduced a method whereby three negatives were taken through suitable screens at one exposure, by means of a specially con structed camera, from which coloured positives were obtained on three films of bichromated pigmented gelatine, these being then stripped and superposed.
Some beautiful results were shown by t he process, but little has since been heard of it. In 1900, Hofmann, of Cologne, follow-9 ing a suggestion made by Ducos du in 1867, perfected a process in which prints are made on three carbon , tissues, containing red, yellow, and blue pigments, and squeegeed into adhesion over each other. That prolific inventor, Szczepanik, has also been responsible for sundry other ingenious methods of colour photography besides that principally associated with his name, and previously mentioned.