348 PLEASANT WA YS IN SCIENCE. 



soon charged with ozone, and a large room can readily be 

 supplied with ozonized air by this process." 



Schonbein set himself to inquire into the properties of 

 this new gas, and very interesting results rewarded his re- 

 searches. It became quite clear, to begin with, that what- 

 ever ozone may be, its properties are perfectly distinct from 

 those of oxygen. Its power of oxidizing or rusting metals, 

 for example, is much greater than that which oxygen pos- 

 sesses. Many metals which oxygen will not oxidize at all, 

 even when they are at a high temperature, submit at once 

 to the influence of ozone. But the power of ozone on other 

 substances than metals is equally remarkable. Dr. Richard- 

 son states that, when air is so ozonized as to be only 

 respirable for a short time, its destructive power is such that 

 gutta-percha and india-rubber tubings are destroyed by 

 merely conveying it 



The bleaching and disinfecting powers of ozone are very 

 striking. Schonbein was at first led to associate them with 

 the qualities of chlorine gas ; but he soon .found that they 

 are perfectly distinct 



It had not yet been shown whether ozone was a simple 

 or a compound gas. If simple, of course it could be but 

 another form of oxygen. At first, however, the chances 

 seemed against this view ; and there were not wanting skil- 

 ful chemists who asserted that ozone was a compound of 

 the oxygen of the air with the hydrogen which forms an 

 element of the aqueous vapour nearly always present in the 

 atmosphere. 



It was important to set this question at rest This was 

 accomplished by the labours of De la Rive and Marignac, 

 who proved that ozone is simply another form of oxygen. 



Here we touch on a difficult branch of modern chemical 

 research. The chemical elements being recognized as the 

 simplest forms of matter, it might be supposed that each 

 element would be unchangeable in its nature. That a com- 

 pound should admit of change, is of course a thing to be 

 expected If we decompose water, for instance, into its 



