336 jDr. Hare's new Galvanic Apparatus, Theory, Sfc. [May, 



dered more capable of producing; them by being still more 

 concentrated. 



If the one be generated more copiously, the other more 

 intensely, the first will move in a large stream slowly, the last in 

 a small stream rapidly. Yet, by narrowing the chaiinel of the 

 latter, Wollaston is supposed to render it more like the former ; 

 that is, produces a resemblance by increasing the supposed 

 source of dissimilarity. 



It has been imagined that the beneficial effect of his contri- 

 vance arises from the production of a continued stream, instead 

 of a succession of sparks ; but if a continued stream were the 

 only desideratum, a point placed near the conductor of a power- 

 ful machine would afford this requisite, as the whole product 

 may in such cases be conveyed by a sewing needle in a stream 

 perfectly continuous. As yet no adequate reasons have been 

 given why, in operating with the pile, it is not necessary, as in 

 the processes of Van Marum and Wollaston, to enclose the wires 

 in glass or sealing wax, in order to make the electricity emanate 

 from a point within a conducting fluid. The absence of this 

 necessity is accounted for, according to my hypothesis, by the 

 indisposition which the electric fluid has to quit the caloric in 

 union with it, and the almost absolute incapacity which caloric 

 has to pass through fluids unless by circulation. I conceive that 

 in galvanic combinations, electro-caloric may circulate through 

 the fluid from the positive to the negative surface, and through 

 the metal from the negative to the positive. In the one case 

 caloric subdues the disposition which electricity has to diffuse 

 itself throuji'h fluids, and curries it into circulation. In the other, 

 as metals are excellent conductors of caloric, the prodigious 

 power which electricity has to pervade them agreeably to any 

 attractions which it may exercise, operates almost without 

 restraint. This is fully exemplified in my galvanic deflagrator, 

 where 80 pairs are suspended in two recipients, 40 successively 

 in each, and yet decompose potash with the utmost rapidity, 

 and produce an almost intolerable sensation *' when excited 

 only by fresh river water. 1 have already observed that the 

 reason why galvanic apparatus, composed of pairs consisting 

 each of one copper and one zinc plate, have not acted well with- 

 out insulation f was because electro-caloric could retrocede in 

 the negative as well as advance in the positive direction. I will 

 now add that, independently of the greater effect produced by 

 the simultaneous immersion of my 80 coils, their power is 

 improved by the proximity of the surfaces, which are only about 



• I do not say shock, as it is more like the pennanent impresMon of a pointed wire ; 

 and when an acid is used, of a hot one. 



-f- That is, with the same mass of conducting fluid, in contact with all the surfaces, 

 instead of being divided into different portions, eacli restricted in its action to one copper 

 «nd one zinc plat^ 



