TRANSACTIONS OF THE SECTIONS. 447 
When one of these cells is connected with a voltameter, no decomposition takes 
place that is sensible, though a feeble current passes. With two a slight extrication 
of gas takes place at first and ceases, though it may be made continuous by reversing 
the direction of the current. Three act steadily: the inactivity of the others is owing 
to what has been called polarization of the electrodes, but which I would rather name 
electrolytic resistance. It may be measured as E in turns of the rheostat, and was, 
with the particular charges which I then used, 2°5 E. Obviously, therefore, two cells 
could not decompose it, for in that case by Ohm’s theory the energy of the current 
pu2E—e5E 
~“2R+rt+y 
(y being the resistance of the voltameter) is negative. 
This antagonist force is, I believe, referred to the accumulation of nascent hydrogen 
and its peroxide on the electrodes; and it seemed likely that the evolution of these 
substances might be promoted by coating the platina with that metal in a state of 
fine division. This was performed by filling the voltameter with chloride of platina, 
immersing in it a positive platina wire, and making the electrodes negative. The case 
was now altered; one cell decomposed feebly with chlorine compounds as charges, 
but decidedly with sulphates; two give 1*1 cubic inch of the mixed gases in five 
minutes. With higher numbers the difference is also decided. The quantities given 
by 3 cells had been 2°5,now 5°5 
6 a3 ? 9°9 o> I 1 8 
6 double ,, 185 ,, 25:3 
My first impression was that the electrolytic resistance must have been lessened, for 
the fact of decomposition implies that n E is greater than e in the formula; but on 
examining it I found that e=E x 2°49. Therefore J infer that the force which thus 
assists the battery in subverting the affinity of oxygen for hydrogen is of such a 
nature that the galvanometer does not take cognizance of it, and therefore is not elec- 
tric. What then is its nature? The only explanation which occurs to me is, that 
the energetic capillary attraction which appears to exist at the surface of this platina 
coating may be, like heat or electricity, convertible into chemical attraction, or that 
the film of water in contact with it being decomposed, the heat evolved by its con- 
densing a new one (for the intensity of this capillary force is very great) may, as in 
Grove’s recent discovery, aid the separation of the gases. I may add that this pe. 
culiar action is more energetic at the positive electrode than the other. I removed 
the coating from one of the plates by filling the voltameter with muriatic acid, and 
making it positive. The surface retained however some of it which could not be re- 
moved. When this was the negative electrode, more gas was evolved than when it 
Was positive. With 2 cells the quantities are 2°18 and 2°68, with 6 cells 8°60 and 
9°12. It maybe added, that in all these cases the resistance of the voltameter itself 
appears to have been the same, the different measures varying from 38 to 35. 
On the Electricity of Tension in the Voltaic Battery. 
By Joun P. Gassiot, F.R.S. 
_The author, referring to a paper presented to the Royal Society in December 1843, 
remarks that the water battery he then used, which with 3520 pairs gave a continued 
series of sparks, is at this time nearly as energetic in its action as at first, merely re- 
quiring to be refilled with water from time to time as it evaporates. 
This was the only arrangement of the voltaic battery by which he was then en- 
abled to exalt the effects of tension so as to obtain the electrical spark before contact 
of the terminals; although with the assistance of an exceedingly delicate gold-leaf 
electroscope, he at that time elicited distinct signs of tension in a single cell of Grove’s 
nitric acid battery, and subsequently in one of copper and zinc charged with sul- 
phuric acid. But in all the different series of experiments described in the paper 
‘referred to, he invariably found that the higher the chemical affinities of the elements, 
the greater was the development of the effects of tension, For instance, to produce 
a certain extent of tension with the gas battery of Grove when charged with oxygen 
and hydrogen, ten or twelve pairs of cells were required; with hydrogen and chlo- 
rine, six pairs ; with chlorine in a single tube and amalgamated zinc as the positive 
