50 Prof. Clausius on the Nature of Ozone. 



these niovin"- atoms, ou coming into contact with the oxide, are 

 able to withdraw the atoms of oxygen which are only feebly 

 combined. This accovmts at the same time for the double effect, 

 . the reduction of the oxide and the disappearance of the ozone. 



The behaviour of ozone is in many respects similar to that 

 of the peroxides. Peroxide of hydrogen, for instance, has, as is 

 well known, a strong oxidizing action, by reason of the facility 

 with which it gives up its second atom of oxygen. If, on the 

 contrary, peroxide of hydrogen be brought into contact with the 

 oxides of the noble metals, or with certain metallic peroxides, a 

 reciprocal reduction takes place. We may in such a case pre- 

 sume that the oxygen-atoms liberated from the peroxide of hy- 

 drogen combine and form molecules with those which are given 

 off from the metallic oxides or peroxides. 



In considering the above-mentioned phsenomenon, the question 

 may arise, why the atoms of ozone, or the easily separable oxy- 

 gen-atoms in a single oxide or peroxide, should not unite with 

 one another with as great a facility as the atoms of two hetero- 

 geneous substances combine together. Various secondary rea- 

 sons, however, may be of influence. In the first place, the state 

 of aggregation must be considered. In a solid metallic oxide or 

 peroxide, the several parts are fixed in position with respect to 

 one another ; and we may therefore presume that the oxygen- 

 atoms do not come into that contact with one another which is 

 necessary for combination. A fluid body, on the contrary, 

 adapts itself better upon a solid one, and its particles possess at 

 the same time the necessary mobility. The same is the case 

 with a gaseous body ; and such a one, in addition, undergoes a 

 condensation on the surface of the solid body. It may, more- 

 over, be the case, that the equally electrified condition of the 

 oxygen-atoms of a definite compound renders them less disposed 

 to combine with one another than with the non-electric ozone, or 

 with the oxygen-atoms of another compound, whose electrical 

 state may possibly be a different one. Moreover, the electrical 

 conductibility of the substance may be of influence, inasmuch 

 as those alterations of the electrical condition which are neces- 

 sary for combination, may take place more easily in contact with 

 metallic bodies than in the interior of badly-conducting bodies. 

 Probably still further reasons might be given in answer to the 

 question proposed ; but those already adduced may suffice, at all 

 events, to show how numerous the influencing circumstances 

 may be, and how vain it must be to expect to find the phseno- 

 mena following some simple law which holds good in all cases. 



Finally, 1 must remark that the density of ozone, as given by 

 Andrews and Tait *, according to whom it would appear to be 



* Proceedings of the Royal Society, vol. viii. j). 4!)8 ; and Phil. Mag. for 

 February, 1858, p. 14G. 



