REPORT OF THE SECRETARY. 107 



mountain above the dust and smoke of its former plateau location, and 

 also to erect a building on the Harqua Hala Mountain, in Arizona, 

 to which the Mount Wilson solar-constant work will be removed in 

 September, 1920. 



Respectfully submitted. 



C. G. Abbot, Director. 

 Dr. C. D. Walcott, 



Secretary, SmitTisonian Institution. 



