Volume 1

On molecular and microscopic science / by Mary Somerville.

  • Somerville, Mary, 1780-1872.
Date:
1869
Catalogue details

Licence: Public Domain Mark

Credit: On molecular and microscopic science / by Mary Somerville. Source: Wellcome Collection.

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    hot tube, it comes out'pure oxygen. According to the experiments of Messrs. Tait and Andrews, oxygen gas loses six eighths of its volume, and becomes.four times moi'e dense by the change; it contracts -more readily with obscure electricity than with the spark. The experiments of Professor Tyndall on the absorption- of radiant heat by gases give reason to believe that ozone is produced by the packing of the atoms of ele- mentary oxygen into oscillating groups, and that heat- ing dissolves the bond of union and restores the ozone to the form of oxygen. Ozone chiefly exists in air that has passed over a great expanse of sea, and the quantity is increased during the aurora, which alone might lead to a surmise of that phenomenon being electric. The change of oxygen into ozone is not the only instance of Allotropism,—that is to say, the existence of the same substance in two states differing from each other in every respect,—for ozone itself is allotropic. Professor Schonbein has discovered that there are two kinds of ozone standing to one another in the relation of positively and negatively active oxygen ; namely ozone and antozone, which neutralize each other into common oxygen when brought into contact. In this x'espect they are analogous to electricity, and, like electricity too, one kind cannot be produced without a simul- taneous development of the other. When a metal, such as silver for example, is oxidized or rusts, it gives polarity to the atoms of oxygen in the atmosphere and divides them into the opposite states of ozone and antozone ; the ozone combines with the silver and msts or oxidizes it, at the same time that the ant- ozone is dissolved in the moistui-e or aqueous vapour in the air and forms peroxide of hj'-drogen. The oxidized or rusted silver, as well as every other oxidized substance, is an ozonide, while the peroxide of hydi-ogen is an ant- ozonide.