98 
SIR B. C. BRODIE ON THE ACTION OE ELECTRICITY ON OASES. 
distributed according to the equation 
4fpS*+io|B 
and r= 2, in which 
2| 3 =r+4[i], 
we have here an example of a third form of decomposition, r— f , in which 
4f =3 r+ 6 B]. 
These various experiments lead to one and the same conclusion, and demonstrate that 
the ozone produced in the electric decomposition of carbonic-acid gas in the induction- 
tube is the same in kind as that produced by the action of electricity upon pure oxygen, 
but that its quantitative reactions are in certain cases, and to a limited extent, modified 
by the circumstances peculiar to the experiment. 
It was of special importance, in reference to the primary object of this investigation, to 
ascertain the combination of conditions most favourable to the production in the unab- 
sorbed gas of a high percentage of ozone. From the numerous circumstances of the 
experiment, and the variety of ways in which these circumstances may be varied and 
combined, this question is of a very complex order, and can only be fully and satisfactorily 
answered by a careful special investigation, which I have not attempted. 
The following experiments, however, throw considerable light upon the problem. 
I. The question which most obviously comes before us is, as to the result of the pro- 
longed action upon the gas of the electricity generated by a coil of high intensity. This 
question is answered by the following experiment, although it did not happen to have 
been instituted in reference to it. A very slow current of pure carbonic-acid gas, care- 
fully dried, was passed through the induction-tube and there submitted to the action of 
the electricity generated by a coil of the above description ; the gas was collected in a 
sulphuric-acid gas-holder. A pipette of this gas was drawn over into the absorption- 
bulb, and there allowed to stand for some time over a strong solution of caustic potash. 
The ozone in this case undergoes an expansion in presence of the alkali similar to that 
which it undergoes by the action of heat. I may observe that I had first tried to 
expand the gas, as in the case of electrized oxygen, bypassing it through a heated tube, 
but had found reason to believe that a small portion of the oxygen present in the gas 
was removed by this operation. The gas was then transferred from the aspirator to a 
eudiometer and there detonated (without any addition of oxygen), the contraction noted, 
and the carbonic acid determined by removal with potash. Two experiments thus con- 
ducted gave the following results : — 
Volume of gas in 
pipette. 
Titre. 
Volume of 
unabsorbed gas. 
249-14 
2-52 
250-5 
64-81 
249-6 
63-77 
The 63-77 cub. centims. of gas from the last experiment, when detonated in the 
