Nature and Strength of the Battery Acid. 121 
ous coppers is a disadvantage, but I do not find that it is any 
advantage; for when, with both the forty pairs of three-inch 
plates and the twenty pairs of four-inch plates, I used papers 
well imbibed with wax%, these being so large that when folded 
at the edges they wrapped over each other, so as to make cells 
as insulating as those of the porcelain troughs, still no sensible 
advantage in the chemical action was obtained. 
1185. As, upon principle, there must be a discharge of 
part of the electricity from the edges of the zinc and copper 
plates at the sides of the trough, I should prefer, and intend 
having, troughs constructed with a plate or plates of crown 
glass at the sides of the trough: the bottom will need none, 
though to glaze that and the ends would be no disadvantage, 
The plates need not be fastened in, but only set in their places ; 
nor need they be in large single pieces. 
§ 17. Some practical results respecting the construction and use 
of the Voltaic Battery. 
1136. The electro-chemical philosopher is well acquainted 
with some practical results obtained from the voltaic battery 
by MM. Gay-Lussac and Thenard, and given in the first forty- 
five pages of their Recherches Physico-chimiques. Although 
the following results are generally of the same nature, yet the 
advancement made in this branch of science of late years, the 
knowledge of the definite action of electricity, and the more 
accurate and philosophical mode of estimating the results by 
the equivalents of zinc consumed, will be their sufficient justi- 
fication. 
1137. Nature and strength of the acid.—My battery of forty 
pairs of three-inch plates was charged with acid consisting of 
200 parts water and 9 oil of vitriol. Each plate lost, in the 
average of the experiments, 4°66 equivalents, or the whole 
battery 186°4 equivalents, of zinc, for the equivalent of water 
decomposed in the volta-electrometer. Being charged with 
a mixture of 200 water and 16 of the muriatic acid, each plate 
lost 3°8, or the whole battery 152, equivalents of zinc for the 
water decomposed. Being charged with a mixture of 200 
water and 8 nitric acid, each plate lost 1°35, or the whole bat- 
tery 74°16, equivalents of zinc for one equivalent of water de- 
composed. ‘The sulphuric and muriatic acids evolved much 
hydrogen at the plates in the trough; the nitric acid no gas 
whatever. ‘he relative strengths of the original acids have 
already been given (1127.); but a difference in that respect 
* A single paper thus prepared could insulate the electricity of a trough 
of forty pairs of plates. 
Third Series, Vol. 8. No. 45. Feb, 1836. 
