Mr. Grove on the Gas Voltaic Battery. 269 



hydrogen, no voltaic effects were produced ; that oxygen and 

 nitrogen produced no effects, but that hydrogen and nitrogen 

 did produce a voltaic current, which I attributed to the com- 

 bination, with the hydrogen, of the oxygen of atmospheric air 

 in solution; this opinion will be further tested in the follow- 

 ing paper. 



The voltaic current generated by this battery I attributed 

 to chemical synthesis, of an equal but opposite kind, in the 

 alternate tubes, at the points where the liquid, gas, and pla- 

 tinum met, and the object of covering the platinum with the 

 pulverulent deposit*, was to increase the number of these 

 points, the liquid being retained upon the surface of the pla- 

 tinum by capillary attraction. 



The point which appeared to me at that time as most im- 

 portant, was the beautiful instance of the correlation of natural 

 forces exhibited by the fifth effect, in which gases by com- 

 bining and becoming a liquid, transfer a force which is capa- 

 ble of decomposing a similar liquid, and causing its constitu- 

 ents to become gases; heat, chemical action and electricity 

 being all blended and mutually dependent. 



The apparatus with which I made the above experiments 

 being composed of some pieces of tubing which happened to 

 be in my laboratory, did not enable me to attain any precise 

 accuracy of measure as to the volumes of gases absorbed, or 

 to prove that Faraday's law of definite electrolysis finds no 

 exception in the gas battery. Since that paper was written I 

 have, after some failures, constructed apparatus by which I 

 have been enabled to verify this law and to extend my re- 

 searches into the nature of gaseous voltaic action. I have felt 

 the more called on to multiply experiments on this subject, as 

 a letter has been published on the gas battery, written by an 

 electro- chemist for whose opinion I have much respect, which 

 attributes its action to a cause different from that to which I 

 assigned it. 



Soon after my original publication I received a letter from 

 Dr. Schcenbein, the substance of which has since appeared in 

 printf . Dr. Schcenbein there expresses an opinion, that in 

 the gas battery oxygen does not immediately contribute to the 

 production of the current, but that it is produced by the com- 

 bination of hydrogen with water. I have recently heard a si- 

 milar opinion to that of Dr. Schcenbein expressed by other 

 philosophers, but I must take the liberty of dissenting from it 

 and of adhering to that which I expressed in my original 



* For the method of effecting this see Mr. Smee's paper, Phil. Mag., 

 April 1840. 



f Phil. Mag., March 1843, p. 105. 



