198 



ON THE PILE OF VOLTA. 



Galvanic pile. 



VIII. 



Obfervations and Experiments relating to the Pik of Volt a. 

 Inn Letter from Joseph Priestley, LL.D, F+R.S. 



To Mr. NICHOLSON. 

 Dear Sir, 



JTXAVING been favoured by Mr. Weatberby Phipfon, a. 



young man of Birmingham, with an excellent apparatus for 



repeating the experiments on the pile of Volta, conlifting of 



fixty plates of copper coated with filver, and as many thin 



rolled plates of zinc, which is a valuable improvement of his 



own, I have had great fatisfaclion in obferving the remits ; 



and though, receiving intelligence of what is doing on the 



continent of Europe io late as I do here, it is probable that I 



fhall be anticipated in my obfervations, I (hall lay them before 



you, and, with your approbation, before your readers, after 



obferving, that I have lately received the fourth volume of 



your excellent Journal, but am ignorant of all that has been 



done fince the publication of it. 



I cannot help expreffing my admiration of the ingenuity 



with which your correfpondents and others have purfued this 



moft curious fubject ; and in general my remits are the fame 



with theirs, though I draw different concluiions from them, 



efpecially with refpecl; to the modern hypothecs of the decom- 



pofition ofzwtcr, which, though almoft univerfally received at 



prefent, I conlider as wholly chimerical, and unable to ftand 



its ground much longer. Indeed, I perceive that doubts are 



entertained concerning it by feveral of your correfpondents, 



and others obferve that thefe experiments give no fupport to 



For the oxlgen it. To me it is evident that they are far from doing fo. For 



does not bear the though it may happen that the inflammable air from the wire 



alledged propor- ° : 1. rr r . , r ~. ., . . , 



tion to the hi- connected with the lilver end ot the pile, be in the proportion, 



drogenj to the dephlogifticated air from the wire connected with the 



zinc end, which that hypothefis requires, it appears that the 



latter comes from the air that is merely held in folution in the 



but arifes only water in which the procefs is made ; lince if, by means of oil 



fromair diflblved U p 0n t } ie wa ter, or a vacuum, accefs to the atmofphere be 



the water. , cut off, the whole production of air ceafes. There is alfo no 



The air ceafes to production of air when the water has been exhaufted of it; 



*flue, if the at- anc [ certainly no good reafon can be given why, if the water 



itfelf 



Its admirable 

 cfFefts not ad- 

 mitted to prove 

 the decompoii- 

 tion of water. 



