OF ARTS AND SCIENCES. 9 



I. 0.2052 grm. of the salt was treated according to the method of 

 Carius and gave 0.0844 grm. of argentic bromide. The fil- 

 trate was freed from argentic nitrate, and the copper precipi- 

 tated by electricity from a sulphuric of nitric acid solution 

 giving 0.0197 grm. of copper. 

 II. 0.2073 grm. treated in the same way gave 0.0864 grm. of 



argentic bromide and 0.0198 grm. of copper. 

 III. 0.1455 grm. gave 0.0138 grm. of copper. 



From these results it would appear that the substance is a basic 

 salt, or, at least, that it is not the normal salt, and in spite of its very 

 promising appearance is not fitted to throw light on the nature of the 

 original substance. We have not thought it worth while, therefore, to 

 examine it more carefully. We may add, that the salt changes color 

 from a lighter to a darker yellow soon after it is prepared, which we 

 are inclined to ascribe to the conversion of 



ClCu 2 [C 6 H 2 Br(N0 2 ) 2 C(C0 2 C 2 H s ) 2 ] 3 



into the corresponding hydroxyl compound by the action of the water 

 in which it is suspended. 



Properties. — The copper salt forms an obscurely crystalline pre- 

 cipitate of a golden yellow color, with a very slight greenish tinge. 

 It is essentially insoluble in water, alcohol, or ether, and is a compar- 

 atively stable substance, as it seems to be unaltered by exposure to 

 the air, or by heating to 100°. Strong nitric acid, even in excess, de- 

 composes it, setting free the bromdinitrophenylmalonic ester. 



Anilidodinitrophenylmalonic Ester, 

 C 6 H 5 NHC 6 H 2 (N0 2 ) 2 CH(COOC 2 H 5 ) 2 . 



This substance was made by mixing the bromdinitrophenylmalonic 

 ester with aniline in the proportion of one molecule of the ester to 

 two of the base. The solid becomes yellow almost immediately, and 

 the action has come essentially to an end after the mixture has stood 

 for a few minutes in the cold. As a measure of precaution, however. 

 we always heated it gently for a few minutes to make certain that 

 all the bromine had been removed. The product was purified by 

 cystallization from alcohol, until it showed the constant melting point 

 118°, dried at 100°, and analyzed. 



