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XXXIII. On some anomalous cases of Electrical Decomposition. 

 By W. R. Grove, F.R.S. ^c* 



WOLLASTON showed, in a well-known experiment f^ that 

 when Franklinic electricity from the prime conductor 

 of an ordinary electrical machine was made to pass from fine 

 points of gold wire sealed into glass tubes and immersed in 

 water, both positive and negative pole gave mixed oxyhydrogen 

 gas, the exact proportions of which are not given. This expe- 

 riment has been subsequently discussed by Ritchie J, Faraday §, 

 and others, but difi'ering as the decomposition in this case does 

 from electrolysis by the voltaic battery, I am not aware that it 

 has been repeated on a large scale, or that anything more than 

 .a mere verification of the fact has been attempted. 



The apparatus constructed by M. Ruhmkorff", which I have 

 described in a paper in the Philosophical Magazine for December 

 last, p. 500, having given me the means of procuring electricity 

 of tension in quantity far exceeding that of the best electrical 

 machine, and having my attention directed to WoUaston's expe- 

 riment by the wires sealed in glass tubes which I used for my 

 recent experiments, I determined to make some experiments 

 similar to Wollaston's, but with the spark from the secondary 

 coil instead of that from the electrical machine. I select the 

 following from amongst many experiments made with this ap- 

 paratus. 



The terminals of the secondary coil consisted of two wires of 

 platinum g\jth of an inch in diameter sealed into glass tubes. 

 One of these coated wires was prepared on purpose for these ex- 

 periments ; and having been carefully sealed into a glass tube, 

 the extremity was ground on a hone until the section of wire 

 formed one surface with the glass. 



The other coated wire had been similarly prepared, but had 

 been used for some time for the experiments in attenuated gases, 

 given in the paper to which I have alluded ; and the extremity 

 of the wire was worn beneath the surface of the glass, a circum- 

 stance which proved of some little importance ||. 



The tubes containing the platinum wires were curved in form 



* Communicated by the Author. 



t Phil. Traus. 1801, p. 431. % Ibid. 1832, p. 282. § Ihid. 1833, p. 23. 



II This result is important in another point of view than that relating to 

 the experiments in this paper, viz. it shows the transmission of matter in 

 electrical discharges, and that even in the aurora borealis experiment, or 

 passage of the spark in highly rarefied gas, solid matter, even such as the 

 dense substance platinum, is given off; thus favouring the theory that the 

 spark is ignited matter, and rendering the hypothesis of a fluid unnecessary 

 for its explanation. 



P2 



