SIB B. C. BKODIE ON THE ACTION OE ELECTRICITY ON GASES. 
101 
electric action, (3) rigorously to dry the carbonic acid employed, (4) to keep the induc- 
tion-tube at a low temperature. These conditions I endeavoured to realize in the fol- 
lowing manner. 
The carbonic-acid gas was generated in a Kipp’s apparatus, and having been washed 
and dried, as in experiment 3 in the last Table, was passed immediately through the 
induction-tube, which was placed in a glass cylinder, surrounded with flannel, containing 
a mixture of ice and salt, by which means the temperature could readily be kept during 
the experiment at from — 10° C. to — 14° C. On leaving the induction-tube the gas 
traversed three bulbs containing anhydrous phosphoric acid (which were permanently 
attached to the tube to preclude the entrance by diffusion of aqueous vapour), and, passing 
through the solution of iodide of potassium contained in the titre-bulb, entered the 
absorption-apparatus, where the carbonic acid was absorbed by a strong solution of 
caustic potash. The gas was passed through the induction- tube in as rapid a current 
as possible consistent with the absorption of the carbonic acid. When a sufficient 
quantity of gas for analysis had been collected in the absorption-bulb, for which several 
hours were required, the experiment was stopped, the iodine separated in the titre-bulb 
was estimated with hyposulphite of soda, the gas contained in the absorption-bulb was 
measured, and the whole or a portion of it transferred to a eudiometer and there detonated 
with oxygen. The oxygen originally present in the gas was assumed to be equal to the 
contraction occurring on detonation. These data supply all the elements necessary for the 
calculation of the proportion of that oxygen converted into ozone in the induction-tube. 
It is not difficult, by this mode of experiment, to effect the conversion of as much as 75 
per cent, of the total oxygen eliminated in the induction-tube into ozone, in which case 
Q 
the ratio qr=4 ; and the gases formed are constituted of ozone and oxygen in the propor- 
tion of two units of the former gas to one of the latter, the matter of the oxygen being 
thus distributed, 2| 3 -j-| 2 ; but it is difficult to increase the proportion of the ozone beyond 
this limit ; however, I have made several experiments, conducted with all possible care, in 
which this limit has been exceeded. The results of these experiments are given in the 
following Table. In column I. is given the total gas unabsorbed by potash; in 
column II. the titre, T ; in III. the contraction on detonation (that is to say, the total 
oxygen), C ; in IV. the ratio, ; and in V. the proportion of the matter of oxygen 
converted into ozone calculated on 100 parts of the total oxygen, as measured by the 
quantity of the matter of oxygen which would be absorbed by a solution of neutral hypo- 
sulphite of soda were the gas passed through such a solution, which has been proved to. 
be a quantity equal to three times the titre of the gas. 
