i^4 On the Identity e/Gdham/m and Elelirkity. 



IV. 



Of) the Identity ofGalvanlfm and Ek&riclty, 3y a Correfpondent. 



Edinburgh, June 20, l8ol. 

 To Mr. NICHOLSON. 

 SIR, 



X HOPE you will not confidcr me as one ftruggling agalnfl: the convidlion of truth, when 

 I inform you, that I have repeated Mr. Cruickfliank's experiment, of charging a vial with 

 Galvanifm fuccefsfully; but am inclined to draw a very different conclufion from his, in 

 confequence of the phenomenon that prefents itfelf, both during the performance of that 

 experiment, and when it is enlarged and extended on the fame principle. 



The mode that I firft ufed, "was that of filling a common vial with fait water, which was 

 plunged in another veflel aitfo filled with fait water ; though no great nicety was ufed, yet 

 fome attention was paid to the furfaces of the two liquors being nearly upon a level, and by 

 that means it very well reprefented an eledrical vial, coated to the fame height within and 

 without ; then the infide was connefted with one end of the pile, and the outfide with the 

 other. After different intervals of time, fome longer, and fome fliorter, the longeft of 

 which extended to feveral hours, the vial was lifted out in one hand intirely from the vefTel 

 in vvhich ic flood, and the tongue applied to the wire connefted with the infide ; the con- 

 flant refult was, that whether it flood for a longer, or fhorter period, a flight (hock, or 

 rather tafle, was felt on the tongue. Expeding to increafe this trifling fenfation, by mul- 

 tiplying the number of the vials, I made a range of a dozen communicating all the infides, 

 and all the outfides together by wire ; after trying this mode by every means my imagina- 

 tion could fuggefl, I could perceive no increafe of power whatever, but only the flight 

 fenfation, perceptible by means of one vial only. 



The conclufion I am inclined to draw from the above fads is, that Galvanifm cannot 

 be accumulated by the fame procefs with ele£lricity, but that merely a fmall proportion of 

 it can be communicated to fluids, and that confequently a marked di(lin£lion fubfifls be- 

 tween them, the Galvanic charge probably not being a fiftieth part of the power refiding in 

 the pile ; whereas the eledlrical charge is oftener many hundred times beyond the power 

 of the machine that imparts it ; and that the former can be increafed only, by incrcafing 

 the original power. 



I have alfo repeated my former experiments of charging an eledrlcal vial through the 

 infulated pile ; and to determine the matter with the greatefl accuracy, I made ufe of 

 Lane's eleflrometer ; when its knobs were fet at a given diftance, by means of the gra- 

 duated wire, the difcharge conflantly took place at the fame number of revolutions of the 

 machine, which-evcr wire was connedled with the jar, provided the machine was in 



equally 



