PAPERS OX CHEMISTRY AND PHYSICS 135 



This would indicate that the zinc salt in the solution had 

 no injurious effect on the solubility of the silver halides, 

 but rather improved it slightly. 



In order to test the qualities of the treated "hypo" as 

 a fixing agent the solution from which the zinc had been 

 removed as well as that containing this metal was sub- 

 mitted to an expert student photographer for use in his 

 fixing bath. He reported that both solutions worked in 

 a perfectly normal manner, and that he could observe 

 no decrease in efficiency as compared with the ordinary 

 solution and no difference in the quality of the product. 



It is planned to continue the investigation along - 

 eral related lines and to the end of making the pr< 

 a commercial success. 



