130 
DE. AJS^DEEWS AJS'D PEOPESSOE TAIT Oy THE 
position of oxygen produced under the latter circumstances, and, although the facts 
connected with its production in these cases have not been studied with precision, yet 
there appears to be no doubt that ozone is actually formed. 
We must in conclusion add, that the few attempts we have made to isolate either of 
the supposed constituents of oxygen have failed. 
We are still continuing to prosecute this inquhy, and hope on a future occasion to 
lay before the Society the results of further experiments which are now in progress. 
Note, added July 12, 1860. 
It having been suggested that a certain amount of the contraction produced by the 
passage of the electrical discharge through tubes containing oxygen might arise from 
the action on that gas of the platinum wires, or of finely dirided platinum, which, as in 
Mr. Gassiot’s experiment, might be thrown off by the action of the discharge, we have 
made the following experiment, in order to ascertain whether such an action could have 
occurred in the conditions under which we operated. Before describing the experiment, 
it may be proper to state, that in the passage of the discharge of the electrical machine, 
there is no visible separation of metallic platinum, as in that of the discharge from the 
induction coil, nor other evidence of the wires being acted on; on the contrary, both the 
wires and tube retain their original appearance after haring been frequently exposed to 
the alternate action of the discharge and of heat. 
A vessel, of the form represented in the annexed figure, was filled 
with pure and dry oxygen. It differs from the tubes usually employed 
only by haring the lower end of the reservoir drawn out into a capil- 
lary tube ah. The platinum wires were inserted as usual, and an 
auxiliary vessel of the same size and form was filled with di'y air. 
After determining the comparative range of the two vessels, their reser- 
voirs were exposed, in the apparatus before described, to a tempera- 
ture of 300° C., in order to bring them as exactly as possible into the 
same condition. When they had cooled, the levels of the acid in the 
siphon tubes were again read, and the silent discharge was afterwpuxls 
passed through the primary vessel till a contraction of twenty-seven 
millims. Avas obtained in its siphon tube. The extremity of the capil- 
lary tube of the reservoir Avas next cut off at a, and the end of the 
siphon tube d, which had the form represented in the figure, was 
dipped under sulphuric acid. The open end at a Avas noAv connected 
Avith an apparatus, which supplied a sIoav stream of carefully dried air, 
and this was alloAved to pass till the ozone and oxygen originally con- 
tamed in the tube were entirely displaced by the dry air. It is obvious 
that by this arrangement the ozone was removed, AAliile the platinum 
Avires and the inner surface of the tube Avere left in precisely the same 
state as after the passage of the discharge. The tube AA^as next sealed off at c, by the 
