MR. GROVE ON THE GAS VOLTAIC BATTERY. 
101 
the liquid in the oxygen tubes had not risen ; in the tubes containing deutoxide of 
nitrogen, the liquid had risen somewhat unequally in the different tubes to an amount 
averaging 02 cubic inch ; in the detached pair it had risen to the same amount ; not 
the slightest voltaic effect was now produced by the terminal wires. 
Experiment 10. — Oxygen and olefiant gas decomposed the iodide, but rather feebly ; 
after the circuit had been closed for twenty-four hours there was still a decomposi- 
tion, which continued, but the action was extremely feeble. Two cells were allowed 
to remain arranged in closed circuit for fifteen days, a third being placed by the side, 
but with the terminals unconnected ; at the expiration of this time the rise of liquid 
in the tubes was as follows : — 
Rise of liquid in cells of closed circuit, 
in tubes of 
Oxygen 0'05 cubic inch. 
Olefiant gas . . . 0’4 cubic inch. 
Rise of liquid in cells of detached pair, 
in tubes of 
Oxygen 0-02 cubic inch. 
Olefiant gas . . . 0'3 cubic inch. 
Rise of liquid apparently due to voltaic action, 
In oxygen tubes . . . (V03 cubic inch. 
In olefiant gas tubes . . (hi cubic inch. 
These quantities are too small to enable any satisfactory inference to be deduced 
as to the equivalents of these gases which contributed to electrolysis ; the more so as 
the rise of liquid Avas not quite uniform, and the action due to solution was so much 
greater than that due to electrolysis. 
I do not feel entitled to draw any other conclusion from this experiment than that 
there was a very feeble voltaic current produced by these gases ; both the remaining 
oxygen and the olefiant gas were unaltered in character. 
Experiment 11. — Oxygen and carbonic oxide produced notable effects upon the 
iodide, and slight symptoms of decomposing water; a few bubbles gathered upon the 
electrodes of an interposed voltameter ; the effects continued ; and at the expiration 
of fifteen days, the following was the state of the tubes in two cells, put aside as in 
the last experiment : — 
Rise of liquid in cells of closed circuit, 
In oxygen tubes . . 0T2 cubic inch. 
In carbonic oxide tubes 0’93 cubic inch. 
Rise of liquid in tubes of detached pair, 
In oxygen tubes . . 0‘02 cubic inch. 
In carbonic oxide tubes 0 ‘7 cubic inch. 
Rise of liquid apparently due to voltaic action, 
In oxygen tubes 0T cubic inch. 
In carbonic oxide tubes . . . 023 cubic inch. 
Before the battery was charged for this experiment, the carbonic oxide had been 
carefully freed from carbonic acid by caustic potash. After action, the liquid gave a 
slight precipitate with lime-water, showing that carbonic acid had been produced by 
p 2 
