Or±0 ANALYSIS OF THE GALVANIC PILF. 



groups composed of the two metals with the wet body be- 

 tween them. Such is the fundamental proposition, with 

 respect to the mode of action of the galvanic pile, which was 

 to be submitted to farther experiments. 

 Conducting fa- The conducting faculty of all the substances of the vege- 

 • C "d T su°bsunces ta ^ e an< ^ antma ^ kinds, that may be employed to separate 

 owing to nuns- the binal groups of metals, for transmitting from one to an- 

 ture * other their individual electric effects, mostly depends on a 



certain quantity of moisture, with which they are usually 

 penetrated. Of this 1 had soon an opportunity of being 

 informed, by an experiment of my friend L)r. Land, who 

 had constantly followed the progress of these researches ; 

 he had constructed a pile similar to mine, except that cop- 

 per phites were substituted for silver plates, which acted also 

 immediately upon the gold-leaf electroscope; but he fouud 

 the following change in it. 

 lxp.2t. Exp. 41V He dismounted this pile, and laid all its parts 



The paper 011 his hearth, before a great fire, so that the pieces of pa- 

 The action di- P er vvere a ^ in0:it smged, and mounting it again in this state, 

 finished. it did not sensibly affect his electroscope: he brought it 

 into my room, and it affected only the electroscope of my 

 condenser. We then dismounted the pile, and laid all its 

 parti on a table for one hour, my hygrometer being about 

 40°, and when again mount**), it acted on the electroscope 

 as it did before the papers had been so thoroughly dried by 

 a great heat. 

 Wii<ornotan This experiment shows, that Mr. Davy was mistaken 

 msulningbody when he thought, " that with respect to electricities of such 



for low inten- tiL^. intensities, water is an insulatim* bodv." On which 

 iities, * 



principle he considered the mode of action of the pi/c under 



the idea of what he calls induction; meaning, 1 suppose, 



something similar to the effect of Voita's condenser, when 



it operates by tlje interposition of silk between the metallic 



plates. It this were the case, pieces of silk, through which 



what he calls induction is readily produced, being placed 



between the binary groups of mclah, should produce a still 



greater effect than paper in its common state, as more i)isu- 



lating; whereas the foregoing experiment proves, that the 



rrVcct abrupt (cases, when paper, by thorough dryness, i> 



reduced to the state of an insulating body. 1 insist on this 



point 



