

XXVIIL] CONCLUSION. 445 



a reason for many of them which up to the present time have 

 resisted all attempts at explanation. I may go further and 

 say, as I have said before, that it demands those very pheno- 

 mena which proved stumbling-blocks to so many investigators, 

 so long as it was supposed that Solar Chemistry was conditioned 

 similarly to our own. 



When the wonderful chemical changes which take place in 

 the sun from cycle to cycle are more widely known, the im- 

 portance of basing our views of the solar economy on both 

 the chemical and physical facts available will be more generally 

 recognised. 



