SOS Voltaic Electricity. 



coloured crowns which are sometimes ohserved rniinrl the sun and 

 moon, agreeing with cxpeiimenls on light and tiie (.onstitution 

 of the atmosphere; and witli observations of the pliiKnomcnamade 

 with all the precision possible." 



The memoirs to be sent in on or before the expiration of March 

 1822. The prize, wh.ich is fii'ty ducats, will be adjiidi^eil at the 

 pubhc sitting, on the aniiiversiiry of Leibnitz, on the ltd of July 

 followirg:. 



XLVllI. InitUigence and Miscellciveaus yf> tides, 



VOLTAIC ELECTRRJTY. 



To Mr. Til loch. 



rp Puris, 17th October 1820. 



Sfu, — JL H K most important of the facts just discovered i)y 

 M. Ampere are the attraction and repulsion of two conductors, 

 or of two portions of the same conductor joining tiie two ex- 

 tremities of a Voltaic pile, and jilaced in a direction parallel 

 to each other : there is attraction or repulsion according to 

 the respective directions of the electric streams, which, in these 

 conductors, are supposed flowing from the extremity which dis- 

 engages oxygen in the decomposition of water, to that which de- 

 velops hydrogen. Attraction, when the two currents move pa- 

 rallel in the same direction. Repulsion, when they Row in con- 

 trary directions. These attractions, and repulsions, are totally 

 and absolutely different from those which take place between 

 electrized bodies in the ordinary way. 



First. Because they take place onlv when the Voltaic circuit 

 ' eitferme,' that is, when the two ends touch. 



Secondly. It is when the extremities, of the same nature, are 

 the nearest to each other, tliat there is attraction, and there is 

 repulsion when they are further removed ; while, on ihe contrary, 

 electricity of the same nature repels, and of opposite natures at- 

 tracts. 



Thirdly. These attractions, and repulsions, take place in 

 yacuo as well as in air. 



Fourthly. When there is attraction, and it is sufficiently 

 strong to make the two conductors approach each other so as to 

 toucli (the wires which formed these conductors v/ere nearly of 

 the dianicter of knitting needles), they remain adhering to each 

 other like two magnets, instead of separating instantly, as would 

 two conducting bodies electrified in the ordinary way. 



M, Ampere showed that the actions between one Voltaic con- 

 ductor and a magnet, as well as those between two magnets, are 

 the same as those he has discovered between two electric currents, 



if 



