1076 Transactions of the A^ferican Institute. 



The negatives and prints were entirely plain, and Mr. Kurtz stated 

 that he exhibited them for the purpose of proving more conclusively 

 that his best results were not " alwaj^s from retouched negatives." 



On motion of Mr. Thomas a unanimous vote of thanks was tendered 

 to Mr. Kurtz for the exhibition of his concave background. 



Mr. Kurtz stated that he did not contemplate patenting his device, 

 but that he intended to enter a caveat for his own protection, and the 

 protection of photographers who might choose to adopt his method 

 of lighting for portrait work. 



Mr. Bierstadt exhibited a collection of Albertypes from the estab- 

 lishment of the inventor of the process. The prints were of various 

 sizes, from a few inches square to twenty by twenty-five inches, and 

 were much admired. 



The Chairman gave a general description of Albert's process, and 

 exhibited a series of prints by the process ; he also spoke of some 

 recent experiments by M. Dehiroin upon the effect of the luminous 

 rays of light. 



It was found that the carbonic acid in leaves of plants was decom- 

 posed ; also, that water was more rapidly evaporated by the yellow 

 and red rays ; also, that there is a relation between the decomposi- 

 tion of carbonic acid and the evaporation of water. 



Mr. Chapman called attention to the publication in " Photographic 

 Mosaics for 1870," of a process for rectifying a disorganized, positive, 

 printing, silver solution, accredited to Mr. England, and stated that 

 he had published the same process some five years ago, corroborating 

 his statement by reading portions of his original publication, and 

 giving date and page of other periodicals in which it might also be 

 found. 



Mr. Hull remarked that he had become quite indifierent to such 

 appropriations of improvements, first brought out in America, he 

 believed it had become a fixed custom with our trans-atl antic 

 brothers. One of his own inventions, some ten years after its exten- 

 sive publication in this country, was patented by a Mr. Bull in Eng- 

 land, and some time later he had seen his siphon print washer very 

 nicely constructed in porcelain and stamped with the patent mark of 

 some enterprising Frenchman. 



Mr. Hull spoke of the very imperfect classification of photographs 

 at the late exhibition of the Institute, where some misunderstanding 

 had arisen from the various constructions put upon the classifying 

 terra '■'' plain ]^'hotograj)hs^'' and for the purpose of having the m.atter 



