ANALYSIS OF THE GALVANIC PILE. 2(>9 



that the divergences of the electroscopes are produced by plus 

 or minus of electric matter only, comparatively with the 

 standard, which is the actual proportional quantity of elec- 

 tric matter possessed by the ambient air; an object con- 

 nected wilh the proof of the fundamental proposition, that 

 there is an absolute distinction between the density, and the 

 expansive power of the electric fluid, 



1. At the beginning of the experiment, the movable elec- phenomena, 

 troscope is placed near that extremity of the conductor, to 



which the dUk, after having received a spark from a Ley- 

 den vial, is to be approximated. At the approach of this 

 positive body within a small distance, the silver lamina of 

 this electroscope diverge as negative', some of their electric 

 matter having receded to the remote parts of the system (by 

 this word I express the conductor and its associated electro- 

 scopes) ; and thus, though the expansive poiver of the elec- 

 tric fiuid has equally increased upon its whole extent, the 

 two remote electroscopes, and in particular that which 19 

 connected with the silver lamina, diverge positively by a 

 certain quantity. 



2. When the silver lamince are made to recede from the 

 positive body along the conductor, their negative divergence 

 gradually diminishes; it ceases at a certain distance, and 

 farther than this begins a positive divergence, which in- 

 creases to a certain maximum; nevertheless the remote elec- 

 troscopes, and m particular that which is in immediate con- 

 nection with the lamince, remain positive to the same degree 

 as at first. The effect, therefore, of withdrawing the lamince 

 has been to remove them out of the atmosphere of vector 

 of the positive body, which, by increasing the expansive 

 power of their electric Jluid, had made a part of their elec- 

 tric matter to abandon them : and it is the electric matter 

 retired from the anterior part of the system, which occasions 

 the positive divergence in the remote electroscopes. 



3. While the movable electroscope is thus removed from 

 the atmosphere of the positive body, if any part of the sys- 

 tem be touched with a small wire held in the hand, the ex- 

 pansive power of its electric Jluid is thus placed in equili- 

 brium with that of the ground, and the divergence ceases 

 in all the electroscopes. Which shows, that, in the parts of 

 the system over which the atmosphere of the positive body 



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