233 Outlines of a Vieiv of Galvanifm. 



C. But increafe of primarv chemical aftion is not the only 

 inoroanic eftecl of galvanifm ; for it changes the nature of 

 this action in a very pecuhar manner. In the oxidating 

 circle with common water, no perceptible quantity of hy- 

 drnwen is evolved, as in common procefi'es ; but an alkaline 

 fubltance appears to be formed at ihe point of contact of the 

 lead oxidable perfeft condu6lor with the fluid. Thus, if zinc 

 and lilver be made to form a circle with diUilled water, hold- 

 iuiT in folution air, for many weeks, a confidcrable oxidation 

 of the zinc is perceived, without the perceptible evolution of 

 gas ; and the water, at its point of contacl with the filver, 

 becomes poireflcd of the power of tingeing screen, red cabbage 

 juice, and of rendering turbidj folution of muriate of mag- 

 iiefia *. 



In the oxidating circles with acids, gas is not onlv evolved 

 from the parts of the conductors undergoing chemical change, 

 but likewil'e from other parts in which no primary action 

 apparently exilts. Thus, when zinc and filver form a circle 

 with diluted muriatic acid, gas is not only given out at the 

 points of cOntaft of the acid with the zinc, but likewife at 

 the place where it is connected wilh the filver f- And in 

 the circle with tin, gold, and diluted nitric acid, nitrous gas 

 is evolved from the gold as well as from the tin *. 



D. Indeed in all the finale galvanic circles, whenever an 

 oxidatmg influence is exerted at one ot the places of contaft 

 of the perfetSl and imperfect condu6tors, a deoxidating aftion 

 appears to be produced at the other place. Thus, when iron, 

 which oxidates rapidly Mhen f )rming a circle with filver and 

 common water, is arranged with zinc and common water, 

 it remains perfe£lly unaltered, whilii: the zinc is rapidly afted 

 upon.. 



§ 6. The phfenomena exhibited by the fimple galvanic 

 circles cannot well be theorized upon, except in tlie laws of 

 their connection with the more complicated and more 

 ftriking galvanic facts. And it is from the difcovery made 

 bv Volta, of the accumulation of Q-alvaniftn onlv, that the 

 inftruments of invcRigation are derived, bv meays of which 

 the nature of this influence is known, and its mofl; important 

 ao'cncies and relations afcertained. 



III. Of Compound Galvanic Circles y or Galvanic Batteries. 



§ 1. The inftruments for accumulating galvanic power, 

 or the compound galvanic circles, are compofed of the fame 

 elements as the fimple circles; but thole elements are dif- 

 pofed in a different form of aggregation. 



* Orisjiiial experracnr, U. + Dr. ^Voll.lflon. 



To 



