12 



PROCEEDINGS OP THE AMERICAN ACADEMY. 



MOLECDLAR VOLUMES OF ClILOKIDES. 



nation of the self-affinities of the several metals, are the small excess in 

 the case of silver, and the larger excess in the case of mercurous chloride. 

 This is quite in accord with the facts ; for argentic chloride is more 

 stable than the oxide, and mercurous chloride easily splits into mercuric 

 chloride and mercury.* 



The case of the hydroxides is especially interesting. 



The density of the hydroxide of zinc has not been accurately deter- 

 mined ; indeed the data concerning cobalt, cadmium, and magnesium are 

 not very trustworthy on account of the amorphous condition of most hy- 

 droxides. It is interesting to note that in this table, where the substances 

 are arranged in the order of the contraction which ensues when hydroxyl 

 combines with the metal, should also be arranged in the electro-chemical 



* Richards, These Proceedings, 33, 9 (1807). 



