352 PLEASANT WA KS IN SCIENCE. 



atom of oxygen. Thus, in the experiment which perplexed 

 Messrs. Andrews and Tait, the mercury only seemed to 

 absorb the ozone ; in reality it converted the ozone into 

 oxygen by removing its third atom. And now we see how 

 to interpret such a result as we considered in our illustrative 

 case. Five cubic inches of oxygen gave up their atoms, 

 each atom combining with one of the remaining oxygen 

 doublets, so as to form a set of ozone triplets. Clearly, 

 then, fifteen cubic inches of oxygen were transformed into 

 ozone. They now occupied but ten cubic inches ; so that 

 the mixture, or ozonized oxygen, contained eighty-five cubic 

 inches of oxygen and ten of ozone. When the mercury was 

 introduced, it simply transformed all the ozone triplets into 

 oxygen doublets, by taking away the odd atom from each. 

 It thus left ten cubic inches of oxygen, which, with the re- 

 maining eighty-five, constituted the ninety-five cubic inches 

 observed to remain after the supposed absorption of the 

 ozone. 



It follows, of course, that ozone is half as heavy again as 

 oxygen. 



But, as Mr. Heaton remarked, "this beautiful hypo- 

 thesis, although accounting perfectly for all known facts, was 

 yet but a probability. One link was lacking in the chain of 

 evidence, and that link M. Soret has supplied by a happily 

 devised experiment" Although mercury and most sub- 

 stances are only capable of converting ozone into oxygen, 

 oil of turpentine has the power of absorbing ozone in its 

 entirety. Thus, when the experiment was repeated, with oil 

 of turpentine in place of the mercury, the ozone was 

 absorbed, and the remaining oxygen, instead of occupying 

 ninety-five inches, occupied but eighty-five. After this, no 

 doubt could remain that Dr. Odling's ingeniously conceived 

 hypothesis was the correct explanation of Messrs. Andrews 

 and Tail's experiment 



We recognize, then, in ozone a sort of concentrated 

 oxygen, with this peculiar property, that it possesses an ex- 

 traordinary readiness to part with its characteristic third 



