98 
MR. GROVE ON THE GAS VOLTAIC BATTERY. 
short, though it required four pairs to decompose water with immersed platinum 
electrodes, yet the platinum in the atmosphere of hydrogen being analogous to an 
oxidable anode, one pair was with this assistance sufficient to decompose water, just 
as one pair of an ordinary battery will decompose water with an anode of copper. 
The nitric acid battery, an account of which I originally published in 1839, having 
shown me the value of highly oxygenated acids and peroxides as voltaic excitants*, I 
determined, with a view of further extending the analogy of the gaseous and metallic 
voltaic batteries, to try the nitric acid as an electrolyte with the gas battery. Therefore, 
Experiment 5, — I charged a battery with hydrogen and nitric acid in alternate 
cells, the nitric acid being only diluted sufficiently to prevent injury to the wooden 
parts of the battery. With this arrangement I found that three cells were capable 
of decomposing water, and thus, here also, the analogy held good, the gaseous 
hydrogen deoxidating the nitric acid in this arrangement, just as nascent hydrogen 
does in the metallic battery. 
I now endeavoured to produce the converse effects, viz. to form a battery in which 
oxygen should be the gaseous element, and be absorbed by an electrolyte having an 
affinity for it. To this end, 
Experiment 6, — I caused a battery of ten cells to be charged, the one set of tubes 
with oxygen and the alternate tubes with solution of protosulphate of iron. This 
battery decomposed iodide of potassium, but was not able to decompose water; the 
tubes which contained the solution of protosulphate represented the hydrogen tubes 
of the ordinary gas battery. The voltaic action caused by oxygen and protoxide 
of iron was, however, but temporary'!'. After a few hours it abated, the iodide was 
no longer decomposed, and the liquid did not rise perceptibly in the tubes containing 
oxygen; the solution when tested by ferrocyanide of potassium gave a blue precipitate, 
indicating the presence of jieroxide, but the greater portion of this was probably formed 
at the expense of the atmospheric air. 
In the last experiments and others, I had observed that a more decided effect was 
obtained when free hydrogen alone was present than when oxygen was alone. In 
my former paper I attributed this to the atmospheric air in solution, and for conve 
nience of arrangement I have hypothetically assumed this explanation in the com- 
mencement of this paper, but the recent letter of Dr. Scekenbein induced me to look 
further into this point. Therefore, 
Experiment 7, — I charged two batteries of two cells each, with hydrogen and dilute 
sulphuric acid in the alternate cells. When tested by iodide of potassium, each 
battery gave notable effects. One of these batteries was then placed, together with 
a cup containing phosphorus, in a shallow vessel of water; the phosphorus was 
ignited and a large glass vessel inverted over the whole; the terminal wires of the 
* See Philosophical Magazine, May and October 1839, pp. 389 and 290. 
t In experiment 26 it will be seen that a continuous current is obtained from oxygen and a liquid (ammonia) ; 
oxygen likewise gives a current with solution of cyanogen, and probably with many organic compounds. 
