60 THE HEHAVIOUR OF HYDRIODIC ACID IN LIGHT. 



light has been ascertained. It has been shown that hydriodic 

 acid in the presence of oxygen is slowly changed to some- 

 rhing else, the cdloiir (if the solutioa due to the liberated iodine 

 nltiniately disappearing. This change is greatly accelerat-ed by 

 light. There is good reason to believe that the process of the 

 change is one of oxidation, but all attempts to reduce this oxida- 

 tion conijuiuud have failed, and the ciaidition in which the 

 iodine exists still remains unsolved. 



In conclusiou, my most hearty thanks are due to Professor 

 Mackay for his vahiable criticisms, and the kind interest he has 

 taken iu this investigation. 



Dalhoi siK r.MVERSiTY. Halifax, N. S. 

 April 2nd, 1908. 



