184 Description of a Carbon Voltaic Battery. 



hours, and at the end of that time I could perceive no sensible 

 diminution of energy. 



The ninety-six pairs, after having been in action some time, 



yielded from the decomposition of water, four cubic inches of 

 mixed gases in twenty-seven seconds, or about nine cubic inches 

 per minute. A series of nine hundred pairs of Wollaston's ar- 

 rangement in this laboratory, (being as is supposed the largest 

 battery on this construction in existence, in which the whole is 

 plunged by one movement,) each zinc plate four by ten inches, 

 gave at the same time, when excited in the usual way, four cubic 

 inches in fifteen seconds. The time was therefore as fifteen to 

 twenty-seven ; but the surface of metals opposed to each other in 

 the larger series, is one hundred and fifty-six thousand square 

 inches, and that in the constant battery is four thousand, two 

 hundred. I infer from this, that cceteris paribus, the new battery 

 must vastly exceed the old form, in all the classes of effects produ- 

 ced, but am unable from the above data to draw any definite ratio. 



The brilliancy of deflagration produced from this arrangement 

 is very great, particularly in the case of a continuous stream of 

 mercury flowing from the narrowed point of a bent funnel, into 

 which is thrust one pole of the battery, and falling on the sur- 

 face of a pair of the same metal connected with the other pole. 

 The inspection of this splendid combustion for several minutes 

 with unguarded eyes, resulted in a severe inflammation, which 

 confined me for a short time to a dark room. 



In the note referred to, in the last volume of this Journal, page 

 393, I stated that a battery of six members of plumbago one inch 

 in diameter, and two inches high, opposed by an amalgamated 

 zinc coil two and a quarter inches in diameter, and two inches 

 high, (equal to thirteen and a half square inches of zinc, and six 

 inches of plumbago, or about one hundred and twenty square 

 inches of opposing surfaces in the whole battery,) gave the re- 



markable result of four* cubic inches of mixed gases from water, 



in a little less than fifty seconds, and maintained fourteen inches 

 of number thirty platina wire coiled into a spiral, at full incan- 

 descence, for nearly an hour ! The following is taken from Mr. 

 Grove's original article describing his battery, shortly after its in- 

 vention. Speaking of his former account of his battery, (before 

 the British Association at Birmingham,) he says, "I underrated 



* Erroneously printed in loc. cit. 5. 



