99 



Groups of cells were made at various times, and tests made upon them. We 

 mention the group set up during March, ISt'o, as typical of all the Cadmium cells. 

 Thev were of the H form (see Fig. 1) and constructed as follows: 



Fij, 1. 



At A tiiere is a quantity of Cadmium Amalgam about one centimeter deep, 

 and covering the platinum wire, the negative terminal. Above this, at i?, there 

 is a concentrated solution of Cadmium Sulphate (CdS04) containing crystals of 

 Cadmium Sulphate. At E there is pure mercury covering the platinum wire 

 which serves as a positive terminal. Above the mercury, at i>, there is a thick 

 paste of Mercurous Sulphate (HgjSO^), reaching as high as the cross tube. The 

 remainder of the space, CC up to the corks FF, is filled with a solution of Cad- 

 mium Sulphate. The tubes are then sealed above the corks in the usual manner 

 by marine glue or some other form of cement. I can not describe here the manner 

 in which these materials were prepared, but can only refer those interested in the 

 subject to a dissertation which I am about to publish concerning my investigations 

 at Clark University. Suffice it to say that the mercury used was some which I 

 had purified a short time before by means of chemicals and distillation in vacuo; 



