482 SIR B. C. BRODIE ON THE ACTION OF ELECTRICITY ON GASES. 
Strength of 
the solution. 
T. 
V. 
S. 
T r 
W 
T-T,. 
v-W 
1 1 
icrl 
S 
T — Tf 
•96 
•7 
8-15 
8-15 
269-55 
268-92 
25-41 
19*83 
0 
1-68 
251-69 
253-85 
8-15 
6-47 
CO © 
iO 
r— t r-t 
2-19 
2-33 
3-12 
3-07 
We thus, through two perfectly independent methods of experiment, arrive at the 
same conclusion — namely, that when a current of electrized oxygen is passed through a 
solution of protochloride of tin, the amount of oxidation effected in that solution by the 
ozone present in the gas is equal to three times that effected by the “ titre” of that gas, 
and also that the gas undergoes a diminution in volume equal to the space occupied 
under normal conditions by a quantity of oxygen equal to twice that “ titre.” 
If the experimental results were perfectly concordant with theory, we should have 
A ! A=A 
T— T ,- 1 + T— T, 
We have also for the value of A, the density of the gas absorbed, as compared with the 
density of oxygen, after subtraction of the “ titre” in these two experiments, as esti- 
mated from the equation 
S — (T — T]) 
v_y i • 
(1) A=A|=0'97, 
( 2 ) A = iff = 0 ' 88 ’ 
against the theoretical value A = l. 
These results depend in each case upon the successful performance of at least five 
independent experiments, each of which again depends upon various other observations. 
The successive performance of these numerous experiments without any considerable 
error or mistake is truly difficult, and we need not be surprised if a certain divergence 
appears between the actual and the theoretical result. 
The various experiments recorded in the three preceding sections constitute a body of 
exact information as to the chemical properties of ozone, through which it may be 
hoped that this important question will be finally removed from the domain of arbitrary 
speculation and brought within the precincts of science. It only remains to consider 
the bearing which these facts have upon the theory of the subject. 
We may first remark that in the total system of experiments no evidence whatever is 
afforded of the existence in the electrized gas of any other “ simple weight” than the 
“simple weight”* |, and the hypothesis of Andrews and Tait as to the decomposition 
of oxygen by the electric discharge has no support in facts. I shall therefore assume 
the unit of ozone to be constituted of some number of these “ simple weights;” and as a 
* Philosophical Transactions, 1866, pp. 792, 805, 810 ; J. Chem. Soc. 1868, yol. vi. p. 367. 
