THEORY OF GALVANISM. 
267 
The discoveries of Mr. Davy, respecting the chemical Davy’s theory 
agencies of the electric fluid , have led him to a theory of the 
Galvanic pile, intended to reconcile, in some degree, the 
hypothesis of Volta with that of the philosophers of our own 
country. It is admitted, by this acute reasoner, that the action that the ehemi- 
of the menstruum, contained in the cells, is absolutely essential to 
cal action 
gives energy s 
the activity of Galvanic arrangements ; and that the two circum- 
stances even bear a proportion to each other. Notwithstanding 
this concession, he is disposed to consider the movement of 
electricity which takes place on the contact of two metals, as but the el. 
, ...... , . . . . . . , of contact is 
the cause originally disturbing the equilibrium ; and the the tirst mover, 
chemical changes as secondary, and chiefly as efficient in resto- 
ring the balance. 
For example, in a pile of copner, zinc and solution of Example. The 
electrical 
muriate of soda, in its condition of electrical activity, the com ener gj es 0 f 
municating plates of copper and zinc are in opposite electrical thc^prmc^pies 
states. And solution of muriate of soda being composed of two and the play 
series of elements, possessing contrary electrical energies, the adSted^into 
negative oxygen and acid are attracted by the zinc, and the consideration, 
positive hydrogen and alkali by the copper. An equilibrium is 
thus produced, but only for an instant ; for muriate of zinc is 
formed and hydrogen is disengaged. The positive energy of 
the zinc plates, and the negative energy of the copper ones, are 
consequently again exerted and thus the process of electro- 
motion continues, as long as the chemical changes are capable 
of being carried on. 
The most obvious objection, which presents itself against the Objections, 
theory of Mr. Davy, is, that if the chemical agents forming part 
of a Galvanic arrangement, be merely effectual in restoring the 
electric equilibrium, no adequate source is assigned of that 
electricity which gives energy to the apparatus. In other 
words we perceive, in such a process, nothing more than a 
constant disturbance of the balance of electricity by the action 
of the plates, and an immediate renewal of it by the agency of 
the chemical fluids. According to the hypothesis, the produc- 
Jouvnal, XXXIV, 161 , that oxidation of the zinc in the pile is not the 
cause of the electricity and its direction. 
T 2 iton 
