THE 

 LONDON, EDINBURGH and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[THIRD SERIES.] 



DECEMBER 1842. 



LXXIL On a Gaseous Voltaic Battery. By W. R. Grove, 

 Esq., M.A., F.R.S., Professor of Experimental Philosophy 

 in the London Institution. 



To R. Phillips, Esq., F.R.S. 

 My dear Sir, 



IN the Philosophical Magazine for February 1839 I have 

 given an account of an experiment in which a galvanometer 

 was permanently deflected when connected with two strips of 

 platina covered by tubes containing oxygen and hydrogen. 

 At the conclusion of my notice, I say, " I hope, by repeating 

 this experiment in series, to effect decomposition of water by 

 means of its composition." The next paper of mine published 

 in the same year contains an account of a battery to which the 

 public has since attached my name, and which led me into a 

 different field of research. 



In reading over my papers lately for a purpose alluded to 

 in my letter of last month, I was struck with the above sentence. 

 My impression was, that I had expressed a hope not very likely 

 to be realized ; but after a few days' consideration I saw my 

 way more clearly, and determined to try the experiment. 



As the chemical or catalytic action in the experiment de- 

 tailed in that paper, could only be supposed to take place, 

 with ordinary platina foil, at the line or water-mark where the 

 liquid, gas and platina met, the chief difficulty was to ob- 

 tain anything like a notable surface of action. To effect this 

 my first thought was to surround the platina foil with spongy 

 platina precipitated in the usual way by muriate of ammonia. 

 This was suggested to me by the known action of spongy platina 

 on mixed gas, which would by its capillary attraction expose a 

 considerable surface of metal and liquid to the action of the 



Phil. Mag. S. 3. Vol. 21. No. 140. Dec. 1842. 2 F 



