SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOLUME 66, NUMBER 7 



Ibobokins 3funb 



THE PYRANOMETER-AN INSTRUMENT 

 FOR MEASURING SKY RADIATION 



BY 



C. G. ABBOT AND L. B. ALDRICH 



(Publication 2417) 



CITY OF WASHINGTON 



PUBLISHED BY THE SMITHSONIAN INSTITUTION 



MAY, 1916 



