ANALYSIS OF THE GALVANIC PILE. Cfl \ 



brinm of expansive power on this group composed of zinc electric states 

 and copper; therefore, the difference observed in their dec- ^c^il cop- 

 tric states must proceed from a difference in the density of per in contact. 

 the fluid. Now, the only hypothesis added in my system 

 to this immediate conclusion from fact is this: that, during 

 their connexion, copper has the property of acquiring more 

 vector than zinc, from that diffused in the ambient air; by 

 which proportional increase of expansive power, the electric 

 fluid on copper is in equilibrium with that on zinc, though 

 with less density, or proportional quantity of electric matter. 

 I have shown also in the above mentioned works, by deduc- 

 tion from experiments, that, when this influence of bodies 

 on each other, by plus or minus of vector, has ceased by suf- 

 ficient distance, each of them possesses instantly, by the ef- 

 fect of the ambient medium, a quantity of vector, propor- 

 tional to its quantity of electric matter; and thus it is, that 

 the modifications produced by zinc and copper on each 

 other, while associated, and their effects on bodies brought 

 into contact with them on the outside of their groups du«« 

 ring their association, are converted into modifications of 

 the quantity of the electric fluid itself. 



After having treated here the theoretical part of the sub- 

 ject more fully than I had done (for brevity's sake) in my 

 first paper given to the Royal Society; in order to be better 

 understood on this subject, very important in natural phi- 

 losophy; I return to the experiments concerning the analy* 

 sis of the galvanic pile, to bring them here to the same point 

 as they were at in that paper. 



Having found, by the experiment related at the end of Contrivance* 



the first part of this analysis, that, by increasing the size ot for em P lo >'»n« 



r j- i • • a great nu ra- 



the plates, the divergence did not increase in the electros- ber of small 



copes, I considered the manner in which a great number of P lates * 

 small plates might be used. I thought then of having 

 a hole in the centre of small plates, in order to thread 

 them with silk in form of chaplcts, alternating the plates 

 with equal pieces of Dutch-gilt-paper. Not having yet 

 any but tinned iron plates for these trials, I formed two such 

 chaplets, each composed of 140 groups, of 0*5 inch diame- 

 ter, and in order to guard them against dust, I enclosed 

 them in glass tubes; but I found, that, when the chaplets 



lay 



