OF ARTS AND SCIENCES. 



93 



Wt. taken. 

 Argentic chloride. 



0.7206 grammes. 

 1.2984 " 

 1.8455 « 



TTt. taken. 

 Argentic bromide. 



0.9313 grammes. 

 0.9421 « 



First series of analyses. 



Wt. found. 

 Silver. 



0.5419 grammes. 

 0.9771 " 

 1.3892 



Wfc. found. 

 Silver. 



0.5352 grammes. 

 0.5424 " 



wt. calculated. 

 Silver. 



0.5425 grammes. 

 0.9777 " 

 1.3889 " 



wt. calculated. 



Silver. 



0.5350 grammes. 

 0.5424 " 



In this connection I publish, by permission, three analyses, made 

 according to this process, by Prof. J. P. Cooke, in determining the 

 purity of a sample of argentic bromide. 



Wt. of argentic bromide. 



1. 4.1450 grammes. 



2. 1.8172 



3. 4.9601 " 



Wt. of silver. 



2.3817 grammes. 

 1.0437 " 

 2.8497 " 

 Mean value . . 



Per cent of silver. 



57.444 

 57.434 

 57.449 



57.442 



Second series of analyses. 



The slight increase of variation between the found and calculated 

 results in this second series of analyses I attribute to a slight volatili- 

 zation of the argentic chloride before the chloride undergoes fusion. 



With the argentic iodide I have only tried qualitative experiments, 

 but I can see no reason why its determination when mixed with either 

 argentic chloride or bromide cannot be accomplished according to this 

 method. 



