OZONE AND ANTOZONE. 167 
very finely divided metallic dust of platinum, or of gold, which was separated 
from the conductors by the electric current, and converted into oxides of the 
metals ; but Schoenbein proved this explanation to be untenable by the experi- 
ment of employing hot points for the issuing of the electric charge into the air. 
Under such circumstances the hypothetical separation of metallic particles and 
their oxidation should be increased; but, upon the contrary, there was no 
smell of ozone at all perceptible. Besides this, ozonized air, when shaken in 
a bottle with water, does not lose its peculiar smell. Hence it is a gas, not 
absorbable by water, but altered in its character by heat. Marignaec and De 
la Rive subsequently performed experiments which seemed to show that ozone 
is pure oxygen. As Marignac was unable to obtain ozone by electricity with 
oxygen unless moisture was present, it was possible that the substance might 
be peroxide of hydrogen, and this hypothesis became highly probable by the 
extended and careful research upon this point by Dr. Williamson. This chem- 
ist prepared ozone by the electrolysis of sulphate of copper, dried it by passage 
over chloride of calcium, and passed it through a tube containing copper turn- 
ings, heated to redness, which had been first oxidized and then reduced in a 
current of carbonic oxide. By the experiment, oxide of copper and water 
resulted. Schoenbein now adopted this hypothesis, having been fortified 
by experiments of his own. At first he regarded ozone as a higher oxide 
(HO;) than Thenard’s peroxide (HO2) of hydrogen; but at last retained the 
latter formula. Schoenbein defended this view pertinaciously, supporting it 
by experiments and by arguments against that of De la Rive, Marignac, Mar- 
chand, Erdmann, Berzelius, Fremy, and Becquerel, who prepared ozone with 
pure oxygen, (obtained from chlorate of potassa, the gas being washed and per- 
fectly dried,) either by the electrical machine or by an induction current. Ma- 
rignac, by acting with ozone upon pure powder of metallic silver, obtained 
nothing but the peroxide of that metal. Hence the conclusion was warranted 
that ozone is oxygen in an allotropic form. Schoenbein’s opinion was based 
upon his view of the halogen bodies, which, like Berthollet, he believed to be 
peroxides of unknown radicals, and from the analogy of ozone, in its chemical 
behavior, to chlorine. He also assumed that no element is known which has 
an action upon the olfactory nerves to call forth the sensation of smell; chlo- 
rine, iodine, and bromine being, as he believes, compounds, while phosphorus 
and arsenie act upon this sense by reason of their passage into the condition 
of oxides. 
Baumert contended that the odorous gas evolved by electrolytic action is 
essentially different from ozone obtained by the electric spark. Its constitution, 
according to this chemist, is HO3; it yields no water to anhydrous phosphoric acid 
until it has first passed through a tube heated to redness, which he supposed 
decomposes the HO;. Baumert, however, in subsequent experiments, acceded 
to the opinion (derived from iheir investigations) of De la Rive, Erdmann, 
Marignac, Marchand, Fremy, and Becquerel, that ozone is an allotropic condi- 
tion of oxygen. 
Schenbein, in 1858, discovered that if to diluted peroxide of hydrogen a 
few drops of solution of acetate of lead be added, or that if ozonized oil of tur- 
pentine be shaken with the same lead salt, peroxide of lead is formed. ‘The 
same reaction takes place when ozonized oxygen acts upon basic acetate of lead. 
When the peroxide of lead thus formed remains in contact with the peroxide 
-of hydrogen, both are reduced; the result being water, protoxide of lead, and 
oxygen. From this reaction, Schoenbein assumed that the oxygen in the perox- 
ides of hydrogen and of lead exists in an opposite condition of polarity, thus: 
+ —~ 
HOO and PbOO, and that by the union of these molecules of oxygen the ordi- 
nary inactive oxygen results. Clausius and De la Rive also imagined a simi- 
lar molecular condition for oxygen. 
