Photographtcal Section Proceedings. 1093 



additional remarks on silver baths, as modified in action by climate 

 and other conditions, and concluded by promising to exhibit at a 

 future meeting some of the proofs from his negatives taken in Peru, 

 at the same time apologizing for having encroached so much on the 

 attention of gentlemen who were a long way in the photographic 

 algebra, while he was floundering among the simple rules of photo- 

 graphic arithmetic. 



Mr. Squier was listened to with the closest attention, and resumed 

 his seat amid the plaudits of his listeners. 



Prof Vanderweyde thought that the glycerine process was befit 

 adapted for the use of travelers. He also explained the method of 

 working a peculiar apparatus for landscape photography, which had 

 been recently introduced in France. 



Mr. C. Wager Hull had known of but one successful use of glycerine 

 in photography, and that was for the purpose of keeping the surface 

 of the plate moist, after development of the image ; thus allowing an 

 opportunity for redevelopment, after returning from the field work. 

 He thought some of the dry processes might be so modified as to 

 answer all the requirements suggested by Mr. Squier, and he believed 

 that many more negatives would be secured, as the trouble and labor 

 of unpacking and setting up apparatus for working, wet plates would 

 often prevent the photographer from securing interesting and impor- 

 tant views, while a dry process would require a halt of but a few 

 minutes when on the march. 



Mr. D. Chapman described a simple method for producing views 

 by attaching the lens to the side of the dark tent, and placing the 

 sensitized plate within the focus without a camera box. 



Mr. A. J. Drummond exhibited several carbon prints which he 

 had made on Swan's carbon tissue paper. He attributed the blister- 

 ing of the films to the imperfect action of the rubber solution used 

 in transferring the print. 



Mr. J, Dixon described a case of the peculiar action of oxalate of 

 chrome and potash, which was used in cleaning glass shades for the 

 microscope. The crystals adhered so firmly to the glass that their 

 removal abraded the surface sufticiently to destroy all polish. 



Mr. John Johnson, of Saco, Maine, gave an interesting description 

 of experiments, in which Mr. Garfield of Boston, Massachusetts, was 

 engaged, with a view of determining the change produced in glass by 

 exposure to sunlight. 



