44 MR. GASSIOT ON THE RELATION OF ELECTRICAL AND CHEMICAL ACTIONS 
and the moment they touched each other, the needle of the galvanometer was 
deflected. 
20. The best definition that occurs to me of a current is that given by Faraday 
in his Third Series of Experimental Researches*. “ By current I mean anything pro- 
gressive, whether it be a fluid of electricity, or two fluids moving in opposite direc- 
tions, or merely vibrations ; or, speaking still more generally, progressive forces 
and in juxtaposition to this, he says'!-, “ If the magnetic effects depend upon a current, 
then it is evident they could not be produced in any degree before the circuit was 
complete, because prior to that no current could exist.” Now it is manifest that, in 
the experiments already mentioned, the voltaic elements have the power of exhibiting 
electric effects at either, and both ends or terminals, before any progression or actual 
perceptible force takes place in the course of the series ; in other words, that static 
effects exist before or independently of currents, but that these effects cease imme- 
diately on currents being developed. 
21. But, in an inquiry like this, we must examine more closely the actual chemical 
action ; for it involves much of the source of controversy between the contact and 
chemical theories ; and I was naturally anxious to discover whether simultaneously 
with these static effects, or perhaps antecedently to them, any chemical action took 
place in the cells of the battery ; and if so, to what amount. 
22. Faraday;};, in the course of that branch of his experimental researches which 
introduced into notice the voltameter, established the most accurate means of mea- 
suring the amount of chemical action in the battery cells, by the equivalent amount 
of chemical decomposition exhibited in that instrument ; he has also directed our 
attention to the fact, that this amount of electro-chemical decomposition depends 
essentially on the current as denoted by the galvanometer. There was every reason, 
with these facts before us, to expect that the battery, which did not produce a current, 
would not evince any degree of chemical decomposition. Recourse was, however, 
had to the test of experiment ; and, instead of introducing the galvanometer, I sub- 
stituted for it a small piece of bibulous paper, saturated with a solution of iodide of 
potassium ; the gold leaves of the electroscope diverged as before, but, however long 
the duration of action, not the least indication of the liberation of iodine was per- 
ceptible. The inference I make from this is, that no definite chemical action took 
place in any cell of the battery, and consequently that the electric effects above 
shown, and which are termed static effects, take place before or independently of the 
actual development of the chemical effects. 
23. I am aware that, in some form or other, this fact has been acknowledged by the 
most strenuous advocates of the chemical theory. Becquerel§ thus adverts to it: — 
“We must conclude, from all the electrical phenomena, that, in almost all cases, a che- 
mical action has taken place; and hence we are led to believe that the latter is the cause 
which exercises the greatest degree of influence over their production; nevertheless, 
* Experimental Researches, § 283. f § 282. + § 510. § Traite de l’Elect., vol. ii. p. 145 ; vol. v. p. 3. 
