Description of a Carbon Voltaic Battery. 



181 



in the frame F F, figure 2, can rest on the edges of the outer 

 cups until the experimenter is ready to continue his observations. 



Fig. 1. 

 a, a, 





In the usual form of Grove's battery, the porous cell is inextrica- 

 bly confined within the zinc plate, which rises on both sides of 

 it, and confines it in one position ; so that there is no way to 

 charge the cells, except by carefully pouring through a funnel, and 

 they must be discharged when done with, by inclining the appa- 

 ratus gradually on one side, until the nitric acid runs out. 

 In the form here proposed, the cups are all filled very expeditious- 

 ly, by pouring into each a measured quantity of acid ; and during 



