444 



Mr. Grove on Voltaic Reaction. 



Fig. 1. 



Fig. 2. 



absorb) this reaction, so another method of effecting the same 

 object would be, to add the reacting to the initial force, which, 

 from the separable character of the former, did not appear 

 impracticable. After sundry devices the following experi- 

 ments realized my views on this subject. 



Experiment 1. fig. 1. — db is a 

 single cell of the nitric acid battery, 

 exposing six square inches of each 

 metal ; v is an ordinary voltameter, 

 each electrode exposing half a 

 square inch, charged with dilute 

 sulphuric acid ; decomposition was 

 allowed to proceed with this ar- 

 rangement for six hours; the bat- 

 tery, for greater assurance of con- 

 stancy, being in this and the two 

 following experiments recharged 

 every two hours; the level of the 

 liquid in the voltameter was carefully marked on the tube. 



Experiment 2. 

 fig. 2. is the same 

 nitric acid battery, 

 d b the same volta- 

 meter Vf but with 

 an interposed pair 

 of large platinum 

 plates, a c, expo- 

 sing each to each 

 forty- two square 

 inches of surface, 

 and immersed in 

 dilute sulphuric 

 acid ; this arrange- 

 ment was also set to 

 work for six hours. 

 A slight evolution 

 of gas had taken 

 place in the volta- 

 meter in this expe- 

 riment, and the 

 water-level was also 

 marked. 



Experiment 3. — 

 The same appara- 

 tus as fig. 2 ; but 

 my assistant was di- 

 rected to change at 



