OZONE. 27 



the iodine from its combination with the potassium and the 

 iodine then instantly acts upon the starch in its usual man- 

 ner and turns the paper blue. At present very little is 

 known of this substance, its manner of production or its econ- 

 omy in nature, yet its connection with oxygen gives it an 

 importance which calls for its recognition in this treatise. 



