100 
SIE B. C. BEODIE ON THE ACTION OF ELECTEICITY ON OASES. 
These experiments confirm the result last obtained, and indicate that the frequent 
repetition of the electric action on the same gas operates in the same direction as the 
prolongation of that action by passing the gas very slowly through the induction-tube — - 
namely, to diminish the proportion of ozone in the gas*. They afford, moreover, a satis- 
factory explanation of the very different amount of decomposition and very different pro- 
portion of ozone formed in experiments made under conditions apparently the same. 
III. Another important question is, as to the effect upon the electric decomposition of 
the presence of moisture in the gas. The following three experiments were instituted 
with this object; and although not made in immediate connexion with the preceding 
experiments, but from another point of view, may find a place here. In experiment 1 the 
carbonic-acid gas was saturated with moisture immediately before entering the induction- 
tube. In experiment 2 the gas was not dried in the usual manner by sulphuric acid, 
but was only partially dried by a short tube containing chloride of calcium, by which 
desiccating agent a large proportion, it is true, but by no means the whole moisture 
in a gas, is removed. In experiment 3 the gas was dried first by sulphuric acid, and 
subsequently by passing it through a tube about 12 inches long, containing anhydrous 
phosphoric acid. The induction-tube was in every case kept at nearly the same tempe- 
rature by immersion in water containing ice. In experiments 2 and 3 five pipettes of 
the electrized gas were employed for the titration and subsequent estimations. In 
experiment 1, where the volume of carbonic acid decomposed was comparatively 
small, eight pipettes of the gas were employed with a view of securing greater accuracy ; 
but the results of that experiment, for the sake of comparison, are calculated on five 
pipettes of the gas — that is to say, the numbers are ■§■ of those actually obtained. 
Experiment. 
I. 
II. 
III. 
IV. 
V. 
1 . 
•48 
21-95 
6*89 
7*37 
7*53 
2. 
2-75 
48-88 
14-09 
16-83 
17*62 
3. 
3-43 
51*47 
13-91 
17*34 
18-42 
From these data the titre calculated on 100 volumes of oxygen as measured by the con- 
traction given in column V. is, in the three experiments respectively, 
(1) . . 6*38, (2) . . 15-6, (3) . . 18*62. 
These quantities are proportional to the numbers 1, 2*45, 3*76, indicating a progressive 
increase in the proportion of ozone formed corresponding to the more perfect desiccation 
of the gas. In experiment 3, where the gas was most completely deprived of moisture, 
55*86 per cent, of the total oxygen formed Avas converted into ozone. 
The conclusion at which I arrived from the preceding experiments was, that the mode 
of conducting the experiment most favourable to the production of a large proportion 
of ozone in the electrized gas would be (1) to operate upon the gas by means of elec- 
tricity of feeble tension, (2) to submit the gas for as short a time as possible to the 
* For the account of similar experiments in the electrized oxygen, conf. Philosophical Transactions, loc. cit. 
p. 447. 
