ACTIVITY ©P A GALVANIC PILE. 305 



the thread immediately quitted the other, but ftuck to it again into a bafm of 

 when I redipped my hand into the bafip ; and fo on alter- ^^'^^"^^ater 



, , * I y T y communicating 



nately. with the pile. 



Exp. 10. I repeated the preceding experiment, fixing a A filver thread, 

 brafs wire, jn order to obtain more firmnefs in the contadl with f"0'«nded from 

 the thread, into a l^Iock of lead, placed on the table on one block of lead on 

 fide of the pi{e. I bent the wire into a qrook, and fufpended ^^^ fable, was 

 from it an embroidering thread, which I placed at a fmall j^,i^h of thepile 

 diftance from the knob of the pile. As often as I held one of when one hand 

 my hands wet againft the bloi k of lead, and dipped the other The bafinf and'** 

 into the water in the bafin, the thread applied itfelf to the the other, 

 button of the pile, and fluck there ; but it quitted it as foon as ;T^"f'^' tonchti 



. ..... tne lead ; but on 



I mterrupted the communication by withdrawing either hand, removing either 

 This experirnent, repeated more than fifty times following, ^^"^» ^^^ ^^^^ 

 was conftantly attended with the fame refult. 



XVIII. 



Experiments on the ASiiviti/ of a Galvanic Pile, in which thin 

 Strata of Air are fubjiituted injtead of ihc Wet Bodies, Bj/ 

 Mr. Dyckhoff*. 



.R. RITTER has obferved f, that all fubftances which, Ritterafleits, 

 when interpofed between the conftituent parts of the pile, ex- ^^^^ moifture i» 

 cite electricity, are adive only fo far as they contain moifture; Voita's pile, 

 and he afierts, that it is impoffible to conftrud an active pile 

 without the intervention of a wet fubftance. I take the liberty 

 to oppofe to this atfertion an experiment, by which it is con- 

 tradided. I conftructed a pile with difks of copper and zinc. But a pile of 

 and little bits of thin green glafs, about the fize of a lentil, three ^°PP^5 ^^^ ^'oc 

 of which I placed triangularly in the intervals that Separated raJd 'by' bits' of 

 the metallic plates. Thus between each pair of metals I had glafs, m ^s to 

 a thin ftratum of air inflead of a wet fubftance ; and the fol- 'f "P°^« f'^^ 



' alone, exhibits 



lowing were the refults : eleftricity j 



1 . A pile of ten pair^, tried hy the condenfer, affected the though only In a 

 eledrometer as powerfully as a common pile of five pairs, thfr f ^^ ^^ 



, rr ' , -m* • /• . /i <?/.>> ir . , HlOn pllc half 38 



* Foigfs Magaxxn fuer dennewvefien lujiand der Naiurkundi,^^]^^^^^ 

 Vol. IV. p. 791. 



f Intelligenzblatt der allgemeinen Littcraturzeitung, 1802, 

 No. 193. 



VoL.VII.— April, 1804. X 2. The 



