358 



PROCEEDINGS OP THE AMERICAN ACADEMY. 



Fig. 2. Apparatus for Reducing the Bromide. 



analysis this bromine was precipitated with an excess of silver nitrate 

 and weighed. In analyses 2, 3, and 4 the cobalt was leached with pure 

 water, and after filtration the bromine was determined in the filtrate. 

 The solutions of the cobalt in dilute nitric acid proved almost entirely 

 free from bromine, that obtained from analysis 4 being entirely so. The 

 silver bromide from these solutions was combined with that obtained 

 from the aqueous extracts and weighed. As it was hard to believe that 

 cobaltous bromide could be enclosed by the reduced cobalt in such a way 

 as to remain unreduced and yet to go completely into solution with ap- 

 parent ease, it was obvious that some foreign bromide must be present. 

 Accordingly the filtrate from one of the precipitates of silver bromide 



