SIE B. C. BEODIE ON THE ACTION OE ELECTEICITY ON GASES. 
473 
the ozone after its passage through the solution of the alkaline hyposulphite is found to 
have lost its special oxidizing properties, and to have no effect whatever upon a solution 
of neutral iodide of potassium. Hence, to arrive at the amount of oxygen actually 
retained by the solution, we have to add the “ titre ” of the gas which is absorbed 
without change of volume to the contraction ; moreover, in one case, namely that of 
hydriodic acid, this oxidation has been actually determined and found by experiment to 
be equal in amount to twice the “titre” of the gas with neutral iodide of potassium. 
In the case of the polysulphide of barium, again, the contraction is exactly equal in 
amount to the “titre” of the gas; and we may conclude from these experiments with 
certainty that, besides that class of oxidations of which examples were given in the last 
section, and which are attended with no change of volume in the gas, ozone is capable 
of acting upon various chemical substances in a totally different, but still perfectly defi- 
nite way, and of effecting an oxidation equal to twice the amount effected in those cases 
where no change of volume occurs, and which oxidation is attended by a diminution in 
the volume of the gas equal to half the volume of the oxygen employed in effecting the 
oxidation. 
Besides this there is in all probability another definite form of oxidation effected by 
ozone, which is represented by the oxidation of hydriodic acid at 0° C., and by the oxi- 
dation of hydrosulphide of sodium, and possibly also by the neutral sulphide of potas- 
sium and neutral sulphide of barium, in which the oxidation effected is equal to twice and 
a half the “titre” of the gas, and the contraction is equal to once and a half that “ titre.’’ 
In the next section I shall bring before the reader yet another definite class of reactions 
of ozone. 
Section IV. 
When the electrized gas is passed through a solution of neutral hyposulphite of soda, 
the gas undergoes a diminution of volume, as in the case of the alkaline hyposulphite, 
but different in amount. In the following Table I have collected the results of various 
experiments made by me at different times upon this subject. The experiments were 
conducted in the way previously described, and the conditions of the experiments were 
very greatly varied. The first four experiments in the Table were made without any special 
measuring-apparatus, the gas being simply collected in an ordinary graduated gas-jar and 
measured. In some cases the gas was passed very rapidly, and in others very slowly, 
through the solution ; the strength of the solution of hyposulphite was also varied from 
an extreme degree of dilution, as in the first four experiments, to a degree of concen- 
tration of ten times that amount ; the temperature also was varied from 0° C. in some 
experiments to 14° C. in others; but none of these variations produced any appreciable 
effect whatever upon the contraction of the gas. 
The numbers in the second column represent the cubic centimetres of oxygen equi- 
valent to the iodine required for titration of 1 cubic centimetre of the solution. About 
30 cubic centimetres of the solution was the quantity usually employed. 
