1172 The Galvanic Battery. [No. 108. 



involves an anachronism, since this instrument was invented some 

 time after the promulgation of Galvani's experiments, and no portion 

 whatever of the credit due to its invention can be claimed for him, it 

 being the result of original and independent investigations by his 

 opponent Volta. In explaining the action of the Battery, Volta 

 assumed that during the whole time the two dissimilar metals were 

 in contact, a certain force was in constant operation, tending to effect 

 the transfer of electricity from the one metal to the other. To this he 

 gave the name of electro-motive force. Thus when zinc, and copper are 

 in contact the alleged operation of this force is to impel the electricity 

 from the copper to the zinc, so as to maintain the latter in a posi- 

 tive state relative to the former, which is itself in this case negative. If 

 therefore the redundant electricity of the zinc be by any means 

 carried off, and the deficiency of the electricity of the copper be 

 supplied from other sources, the electro-motive force will immediately 

 renew this difference of condition, and thus maintain a continual 

 current of electric power, flowing always in the same direction. The 

 office of the fluid in a Battery, according to Volta's theory, is simply 

 to conduct the electricity from one metal to the other, and its conduct- 

 ing power determines the effective quantity of electricity which 

 actually circulates in the Battery. The force ultimately generated was 

 conceived to be the sum of all the forces acting in each cell separately, 

 since the impulses given by the electro-motive force to the circu- 

 lating electricity, were all in the same direction, and each added 

 its effect to that of the preceding ones. Hence then the interposition 

 of any substance between the two poles of a Battery subjected it to 

 the influence of this powerful electric current. The chemical action 

 of the fluid on either of the metal plates was considered by Volta as in 

 no way connected with the origin of the electricity developed, and his 

 theory consequently took no cognizance whatever of its existence. It 

 was soon however observed, that in thus neglecting chemical action, 

 Volta had committed an important, indeed a fundamental error, since it 

 was found that the quantity of Galvanic effect was always in propor- 

 tion to the energy of the chemical action, and that the extent of surface 

 of contact between the metals, had no relation to the quantity of elec- 

 tricity developed. It was farther found, that metals did not invariably 

 stand in the same electrical relation to each other, but that this rela- 



