SIK B. C. BEODIE ON THE ACTION OF ELECTRICITY ON GASES. 
99 
manner mentioned, underwent a diminution in volume of 19*58 cub. centims., and 40*14 
cub. centims. of carbonic acid were formed, leaving a residue of 4*05 cub. centims. ; the 
theoretical volume of the oxygen is 19*9 cub. centims. We may hence infer that 
230 cub. centims. of carbonic acid were passed through the induction-tube. Further, 
out of every 100 volumes of carbonic acid passed through the induction-tube, 17*4 volumes 
were decomposed. The iodine-titre on the same 100 volumes was Tl, and the iodine- 
titre on 100 volumes of oxygen formed was 12*8. 
Now if these numbers be compared with those found in the previous experiments 
given on page 86, say with experiment (3) there given, it will be seen that although the 
proportion of carbonic acid decomposed is increased tenfold, the iodine-titre, as esti- 
mated on 100 volumes of oxygen, is nearly the same in the two experiments — that is to 
say, the result of the electric action, after a certain point has been reached in the decom- 
position, is simply to decompose the carbonic-acid gas without effecting any corresponding 
increase in the proportion of ozone. It is therefore to be inferred that the prolonged 
action of a powerful coil is by no means favourable to the object of these experiments. 
II. I now proceeded to ascertain the result of repeating the electric action upon the 
same gas. This was effected by placing the induction-tube between two sulphuric-acid 
gas-holders, and passing the electrized gas forwards and backwards between the gas- 
holders in the manner elsewhere described in the case of an analogous experiment with 
electrized oxygen *. The gas was thus passed ten times through the induction-tube. An 
undetermined quantity of the electrized gas was then passed through a solution of iodide 
of potassium, and collected as usual in the absorption-bulb. When the absorption of 
carbonic acid was complete, the volume of unabsorbed gas was measured. The oxygen 
was then absorbed by pyrogallate of potash, the gas again measured, and lastly deto- 
nated in the eudiometer with excess of oxygen. 
The second experiment, given below, was made in a similar manner, all the conditions 
being preserved as nearly as possible the same as in that just described ; but the carbonic 
acid was passed once only through the induction-tube immediately from the vessel in 
which it was generated. The coil employed in these experiments was of high intensity. 
In column I. of the Table below the titre of the gas is given ; in II. the volume of 
gas after absorption of the carbonic acid; in III. the volume absorbed by pyrogallate 
of potash ; in IY. the sum of the gas absorbed by pyrogallate and the titre of the gas ; 
in V. the contraction on detonation with oxygen. 
Experiment. 
I. 
II. 
III. 
IV. 
V. 
1 . 
3*18 
58-03 
16-89 
20-07 
20-27 
2. 
3*55 
44-58 
12-21 
15-76 
16-18 
From these data the titre calculated on 100 volumes of the oxygen formed in the two 
experiments respectively is 
(1) . . 15*6, (2) . . 21*9. 
* Philosophical Transactions, loc. cit. p. 447. 
