388 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



Eatio of Stroxtic Bromide to Silver. 

 Second Series Abrahall's MetliOQ 



Ratio of Argentic to Strontic Bromide. 



Id many of the preceding determinations the bromide of silver 

 resulting from the decomposition was weighed. In every case a slight 

 excess of silver nitrate was added, to render the argentic bromide 

 wholly insoluble in the filtrate. The very slight amount which may 

 have been dissolved by the wash water during its brief contact with 

 the precipitate was not considered. The precipitate was collected 

 upon a Gooch crucible; and the traces (0.04 to 0.2 milligram) of 

 asbestos carried through were collected upon a small washed filter, 

 ignited separately, weighed, and added to the gain in weight of the 

 crucible. From this was subtracted the loss in weight of the precipi- 

 tate upon fusion in a covered porcelain crucible. A description of 

 the dark room used for the experiments, and many other precautions 

 and details, will be found in other papers.* The results are tabulated 

 below. 



* These Proceedings, XXVIII. 24; XXIX. 74. 



