OF ARTS AND SCIENCES. 



249 



result was calculated as argentic bromide ; but in some cases they were 

 determined separately. The presence of phosphoric acid in the dis- 

 tillate is especially unfortunate, because of the uncertainty which it 

 introduces in the end point of the alkaliraetvic reaction. 



On the other hand, quantitative combustion after the usual method, 

 and calculation of the acetic acid from the carbon dioxide formed, is 

 not easy because of the presence of the large amount of bromine. 



Analyses of Cu(NH3)nBrC2H302. 



0.0685 gr. of the substance yielded 0.01865 gr. of copper upon 



electrolysis. 

 0.1446 gr. of the substance distilled with caustic potash required 



12.16 c.c. of a decinormal acid solution for neutralization. 

 0.08485 gr. of the substance yielded 0.06705 gr. of argentic 



bromide. 

 0.3173 gr. of the substance yielded 0.2518 gr. of argentic 



bromide. 

 V. The distillate from a mixture of phosphoric acid and 0.2311 gr. 



of the substance required 10.11 c.c. of decinormal alkali for 



neutralization. Approximately corrected for the alkalimetric 



equivalent of the argentic phosphate and bromide obtained from 



the distillate this amount becomes 9.90 c.c. 



II 



III 



IV 



Many other analyses were made of subsequent preparations, in order 

 to be sure of the identity of the crystals prepared in different ways. 

 It is considered unnecessary to publish these, since they agreed essen- 

 tially with those given above. 



