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SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOLUME 93, NU;MBER 7 



THE CHRISTIANSEN LIGHT FILTER: ITS 

 ADVANTAGES AND LIMITATIONS 



(With Two Plates) 



BY 



E. D. McALISI'tR 



Division of Radiation and Organisms, Smithsonian Institution 



(Publication 3297) 



CITY OF WASHINGTON 



PUBLISHED BY THE SMITHSONIAN INSTITUTION 



APRIL 2, 1935 



