£>83 ^N GALVANISM, 



AbfiraSi' of a Memoir on Galvanifm, fent to the National Infii- 

 tute by Mr. Rittek, of Jena.f 



Erman dlfcover- JL O form a juft idea of thefe refearches, it is necefiary to 

 ^crfea coT- '"™" ''^^^^ ^° "^'"^ ^ difcovery made by Mr. Erman of Berlin, about 

 dudor would two years ago, and fince repeated by Volta before the galva- 

 take theelec-^ pj^ committee of the Inftitute. 



infulated pile. If an eledlric pile, the fuperior pole of which is pofitive, 



and become g^d the inferior negative, be infulated, and a communication 



one*^^end + , the 's made between thefe two poles, by means of an imperfect 



other — . conductor, as for inflance, a flip of paper wetted with pure 



water would be for fuch fmall quantities of electricity ; each 



moiety of this flip would take the eleftricity of the pole with 



which it communicated; the upper part would be pofitive, 



the lower negative. 



If this be re- Now let us conceive this imperfed conductor to be removed 



pioved by a by an infulating fubftance, as a glafs rod: the equilibrium be- 



glafs rod, its tween the two extremities will not be reflored inftantaneouOy, 



Muilibrium will . „ . , ■ r r ■ 



nutbereftored but they will remain politive and negative tor lome time, as 

 at once j when they communicated with the two poles of the pile. 



duall ^^^^ difference will gradually diminifti in proportion as the 



oppofiteeledricitics recombine, and their a6lion, being neu- 

 tralized, will foon become altogether imperceptible, 

 h* Mr ^'^^ fundamental experiment of Mr. Ritter is precifely re- 



Ritter fubiVi- ducible to this; he merely fubftitutes for the flip of paper, a 

 tutes a pile of pj|^ compofed of diflis of copper and wet pafteboard. This 

 pafteboard in pile, incapable itfelf of fetting eledricity in motion, at leaft if 

 alternate pieces, y^^ (uppofe all its component parts homogeneal, is charged by 

 communication with the pile, like the flip of wet paper above- 

 mentioned. 

 Weak elearici- ^^^^ there is an elfentlal difference in the refults. It appears 

 ty, like light, that electricity, when weak, experiences, like light, a kind of 

 ft^ly"from one difficulty in palling from one furface to another: at leaft this 

 furface to feems to follow from the experiments of Mr. Ritter, as he him- 



H°n^e Mr ^^^^ obferves. The electricity introduced into the pile made 

 fitter's pile with one metal alone, experiences therefore fome refiflance in 



remains charged paflfmg from the metal to the pafteboard; and this obftacle in- 

 fer fome time i '^ ° ^ 



* Bulletin des Sciences, No, 79, p. 145, October, 1803. 



crcafes. 



