90 PROCEEDINGS OF THE AMERICAN ACADEMY. 



solved in ten cubic centimeters of commercial acetic acid, with the 

 addition of twenty cubic centimeters of water; the two solutions thus 

 formed were mixed, and fifteen cubic centimeters of aniline were added 

 to the mixture. In about half an hour fine brown crystals began to sep- 

 arate out, and these crystals proved to be cuprianiline acetobromide. 

 Subsequently a great deal of time was expended in attempting to repeat 

 this experiment, with continued failure. At last a few of the original 

 crystals were sprinkled upon the surface of a mixture like the one just 

 described, at the time when the crystals were expected ; and a large 

 mass of the long sought for substance immediately separated. The 

 reasons of the inconsistency of the first success and the subsequent 

 failures remains to be discovered. It is possibly connected with vari- 

 ations in temperature. 



The new compound is nearly insoluble in alcohol and glacial acetic 

 acid, and is partially decomposed by water. Potassic hydroxide re- 

 moves all the bromine from it only with difficulty. It is easily broken 

 up by concentrated nitric acid, but not until heat has been applied. 



Because of the stability of the compound it was necessary to deter- 

 mine the bromine in a rather elaborate manner. The sample was in- 

 timately mixed with a large amount of sodic carbonate in a porcelain 

 crucible, covered with a thick layer of the same salt, pressed down 

 very thoroughly, and very gradually brouglit to a red heat. As the 

 mass contracted, more sodic carbonate was sprinkled around the edges 

 of the mixture, to prevent the escape of a trace of bromine. The 

 fused mass was dissolved in hot water, and the sodic bromide was 

 filtered off and determined as usual.* 



Analyses of Cu(C6H7N)2C2H302Br. 



I. 0.2100 gram of the first sample of substance yielded 0.0343 gram 

 of copper upon electrolysis. 

 II. 0.1768 gram of the first sample of substance yielded 0.0860 gram 

 of argentic bromide. 



III. 0.1743 gram of the second sample of substance yielded 0.08GG 



gram of argentic bromide. 



IV. 0.1232 gram of the second sample of substance yielded 0.0600 



gram of argentic bromide. 



* This method was found to give the same results as that of Carius with 

 these compounds. Of course the method would not answer if the bromine were 

 directly combined with carbon. 



