268 Mr. Howldy on Combust ion by the Electric Spark. 



ceeded in the spring of the following year to repeat these ex- 

 periments of the Germans, and to puisne the inquiry further. 

 By the application of an excited glass tube to phosphorus, 

 Dr. Miles set it on fire. And Dr. Watson fired not only in- 

 flammable air, but gunpowder, by the agency of the electric 

 spark, when it had been previously ground with a little cam- 

 phor, or a few drops of any essential oil : he also succeeded 

 in discharging a musket, and inflaming turpentine and balsam 

 of capivi, by the electric spark. 



While philosophers were prosecuting their inquiries on this 

 subject, the important discovery of the method of accumulating 

 electricity upon the surface of glass was made, or at least 

 first correctly ascertained, at Leyden in Holland. But the 

 augmented electrical power which this discovery placed in their 

 hands, served, at first, to create only surprise, wonder, or 

 terror, in those who personally experienced the singularity and 

 violence of its action. After the tumult into which the minds 

 of philosophers were thrown by the shocks of the Leyden 

 phial had subsided, they began to try what effects it would 

 produce on other bodies. It is remarkable, however, that they 

 did not resume and prosecute with much care the inquiry in 

 which they were engaged, at the period when the brilliant dis- 

 covery of the power they now possessed was made. 



It is equally remarkable that the inquiry has not been pro- 

 secuted by later philosophers with much attention, if the ap- 

 plication of. the electric charge to inflammable gaseous mix- 

 tures and to the combustion or oxidation of metallic wires be 

 excepted. But I think the maimer in which the electric fluid 

 has been constantly and universally applied to inflame or ex- 

 plode combustible bodies is the principal cause why the list 

 of those bodies which have actually undergone the above pro- 

 cesses by its agency, is so scanty. As I have practised, for a 

 considerable time, a new method of producing the combustion 

 or explosion of inflammable bodies by electricity, and have 

 successfully extended it to several not previously subjected 

 to the agency of the electric fluid, I intend to communicate to 

 the public an account of it, through the medium of your 

 Journal, provided you shall think its admission will add a lit- 

 tle to the little already known on the subject. 



The method is, in fact, founded on the same principle as 

 the method of inflaming gunpowder, which 1 lately communi- 

 cated to you, and is similar to it; but it requires, in most 

 cases, a verv different arrangement of the substances which are 

 to be subjected to the agency of the electric fluid. And the 

 experiments in general, demand a pretty exact estimate of the 

 force of the charge, and a nice adjustment of the apparatus, 



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