in Chemical Combinations. 



499 



solution employed was one consisting of 3 parts of crystallized 

 sulphate of zinc and 8 parts of water, weighing 3 lbs. 2 oz. The 

 electrodes were plates of platinum and zinc, each plate exposing 

 an active surface of about 8 square inches. At the conclusion of 

 each experiment, oxide of zinc was thrown into the solution to 

 replace that removed by electrolysis, in order to prevent the zinc 

 electrode from being acted upon by free acid. 



Table IX. — Experiments on the Heat evolved by the Electrolysis 

 of Sulphate of Zinc. Pile of 7 cells. 



Table X. — Experiments on the Heat evolved by the Standard 

 Silver Coil. Pile of 5 cells. 



The following tables give the results of the experiments for 

 ascertaining the capacity for heat of the jar of solution. 



2K2 



