On Thursday night, ab the Union Church Lecture Hall, Dr. Reid and Mr. Chaumont gave a demonstration of nega~ tive making with what may be termed rival developers. Dr. Reid used pyro-soda, wh ¥ be termed the standard of English developers, and Mr. Chaumont diamidophenol, one of the new coal tar products much in use on the Continent, where these newer developers are in great favour. Negatives produced by pyro-soda are generally not so dense to look at, but the deposit is very non-actinic, and vigorous prints are usually to be obtained. The deposit from diamidophenol ix black to look at, but not very nonactinic, and the prints are often found to be soft and sometimes flat, though in experienced hands both produce excellent results. Much interest was shown in the rapid appearance of the image, which came up almost immediately. the diamidophenol was flowed over the plate, while the pyro took nearly a minute to produce any result. The total time before development was completed was, however, very nearly the same with both. It was evident from its characteristic production of detail first and then density, that less exposure was needed for a plate when diamidophenol was intended for uso as developer, and. therefore it is a suitable one for snap shots, the usual production of the ama-tour.' Tt has the further advantage that both bromide and guslight papers can developed with it, which is not the case with pyro, the resulting colour with the latter not being a pleasing one. Pyro can sometimes be used for two plates in sue-cession, but this is risky, as stains may be produced on the second one. Diamidophenol can be safely used for some eight plates in succession, the only effect of repeated application being a slower action.
Mr. Dumfries gives a demonstration to-morrow with bromide and gaslight papers, and will use diamidophenol at the following meeting Mr. Hearson will open a discussion on stereoscopic, photography, and on the 18th December the Society will hold a social evening and exhibition. The musical programme is al in hand, some nine of Shanghai's leading vocalists having consented to sing, and should the pictures come up to the standard of the entertainment, the Society should have such an evening that swill cause it in future to rank as being as important as it is now energetic.
Text read from the printed page and cleaned; old type leaves the occasional error.