£6(5 ANALYSIS OF THE GALVANIC PILE, 



Now this synthesis of the above fundamental experiments 

 is the real fact; as will be seen from direct experiments in 

 the following paper, of which I shall give here only the ge- 

 neral results, 

 proved by ex- I 7 or these experiments I u&e a horizontal pile, which I 

 pcameuu hwe called column, with a gold leaf electroscope at each 

 extremity; and I have also a detached electroscope, which 

 may bt- applied and observed a" every point of the column. 

 The following are the observed phenomena.—]. When the 

 state of the ambient air is such, that in the insulated co- 

 lumn, the divergence is equal at both extremities, the mid- 

 dle point in its length is zero, as represented in Table I, in 

 which, as well as in the two others, the terms are to be con- 

 sidered only as equidistant points, whatever be the number 

 of the groups. — 2. When B communicates with the ground 9 

 the first plate only at this extremity is zero, and the positive 

 state is gradually increasing towards A : the middle point is 

 plus* of the same quantity (f ensibly) as it was at A in Ta- 

 ble 1, aud the divergence plus is doubled at A; a state re- 

 presented in Table II. — 3. When A communicates with the 

 ground, all the effects are reversed: the first plate only at 

 A is zero, and the negative state is gradually increasing to- 

 wards B : the middle point is now minus, of the same quan- 

 tity (sensibly) as it was at B in the case of Table I, and 

 the quantity mhms is doubled at B; a state represented by 

 Table ill. I do not know any theory on invisible causes, 

 which more exactly follows the visible effects, 

 Phy3ical cnu>e What remains to be considered is the physical cause of 



of these t he- ^ ese phenomena, all originating in this circumstance, that 

 nomena. l t -** . " 



when zinc and copper are in mutual contact, zinc possesses 



more electric Jluid, and copper less, than in another situa- 

 tion. In my first .paper delivered to the Royal Society, i 

 explained this effect by analogy with the phenomenon of 

 the different capacities of bodies for the Jluid cause of heat ; 

 but having here entered into an explanation of the nature 

 of the electric Jluid, I shall derive analogies from the sub- 

 ject itself. 

 Most electric Most oP the electric phenomena manifested in our expe- 



phenoinena lm ients depend on the distinction, which I have established, 

 depend on the r , _ ■ _ .... 



i( nsity of the between the density of the electric Jluid, consisting in *ae 



flaU1 ' nronortional quantity of electric matter and its expansive 



power, 



