744 PHILOSOPHICAL TRANSACTIONS. [ANNO 1800. 



XVII. On the Electricity excited by the mere Contact of Conducting Substances 

 of different kinds. By Mr. Alex. Folta, F. R. S. Prof, of Nat. Philos. in the 

 University of Pavia. From the French, p. 403. 



The chief of these results, and which comprehends nearly all the others is the 

 construction of an apparatus which resembles in its effects, viz. (such as giving 

 shocks to the arms, &c.) the Ley den phial, and still better electric batteries weakly 

 charged ; acting continually, or whose charge, after each explosion, recharges 

 itself again ; which in short becomes perpetual, from one infallible charge, from 

 one action or impulse on the electric fluid ; but which besides differs essentially 

 from the other, by thi6 continual action which is proper to it, and because that 

 instead of consisting, like the ordinary phials and electric batteries, in one or more 

 isolated plates, or thin layers of those bodies deemed the only electrics, and armed 

 with conductors or bodies called non-electrics, this new apparatus is formed only of a 

 number of these last bodies, chosen even among the best conductors, and so the far- 

 thest removed, according to the usual opinion, from the electric principle. This asto- 

 nishing apparatus is nothing but an assemblage of a number of good conductors of a 

 different kind, arranged in a certain manner. Thus, 30, 40, 60, or more pieces 

 of copper, or better of silver, each applied to a piece of tin, or still much better of 

 zinc ; and an equal number of layers of water, or of some other liquid which may 

 be a better conductor than simple water, as salt water, lye, &c. or of bits of card 

 or leather, &c. soaked in such liquids. Of such layers, interposed between each couple 

 or combination of 2 different metals, one such alternate series, and always in the 

 same order, of these 3 kinds of conductors, is all that constitutes M. Volta's new 

 instrument ; which imitates so well the effects of the Leyden phial or electric bat- 

 teries ; not indeed with the force and explosions of these, when highly charged ; 

 but only equalling the effects of a battery charged to a very weak degree, of a 

 battery however having an immense capacity, but which besides infinitely surpasses 

 the virtue and the power of these same batteries ; as it has no need, like them, of 

 being charged before hand, by means of a foreign electricity ; and as it is capable 

 of giving the usual commotion as often as ever it is properly touched. This appa- 

 ratus, as it resembles more the natural electric organ of the torpedo, or of the elec- 

 tric eel, than the Leyden phial and the ordinary electric batteries, M. Volta calls 

 the artificial electric organ. For the construction of this instrument, M. V. pro- 

 vides some dozens of small round metal plates, of copper, or tin, or best of silver, 

 about an inch in diameter, like shillings or half-crowns, and an equal number of 

 plates of tin, or much better of zinc, of the same shape and size : these pieces he 

 places exactly one upon another, forming a column, pillar, or pile. He provides 

 also as many small round pieces of card, or leather, or such like spongy matter, 

 capable of imbibing and retaining much of the water, or other liquid, when soaked 

 in it. These soaked roullets or circles are to be a little less in diameter than the 

 small metal discs or plates, that they may not jut out beyond them. All these 



