292 Mr. Gassiot on the relation of Electrical 4* Chemical Actions 



] 9. This experiment was, however, of too much importance 

 to be passed over without adopting every means of making it 

 unexceptionable. Two trays from the battery, being a series 

 of 160 cells, were removed and insulated, by being supported 

 on stout varnished glass pillars twelve inches high ; the whole 

 being placed upon an Arnott's stove in which a fire had been 

 kept burning for several hours. The galvanometer was in- 

 terposed between the zinc terminal of one tray and the copper 

 terminal of the other; and the extremities of this reduced 

 series were arranged so as to exhibit the same effects of elec- 

 trie tension which we have seen in the entire series ; but not 

 the slightest indication of dynamic action could be detected 

 by the galvanometer. The action of the instrument I used 

 could not be in fault ; and some idea may be conceived of its 

 extreme delicacy, when I state that, with one cell of the gas 

 battery* I have obtained a steady deflection, whilst a resist- 

 ance of twelve miles of thin copper wire was interposed in the 

 circuit; when the electroscope (fig. 6) was used, cd being re- 

 spectively connected with N and P of battery, the gold leaves 

 b b' were attracted ; 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 f. "By current I mean anything progressive, 

 whether it be a fluid of electricity, or two fluids moving in op- 

 posite directions, or merely vibrations ; or, speaking still more 

 generally, progressive forces;" and in juxtaposition to this, 

 he says J, " 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 al- 

 ready mentioned, the voltaic elements have the power of ex- 

 hibiting 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 immediately 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 the- 

 ories; and I was naturally anxious to discover whether simul- 

 taneously with these static effects, or perhaps antecedently to 

 them, ani/ chemical action took place in the cells of the battery \ 

 and if so, to what amount. 



• Philosophical Transactions, 1843. 



t Experimental Researches, § 283. J lb. § 282. 



