CONTAINING 



Atmometry and the Porous Cup. Atmometer I. 



Burton Edward Livingston 21 



Natural Reforestation in the Mountains of Northern Idaho 



Harry B. Humphrey and John Ernst Weaver 31 



Books and Current Literature 48 



Notes and Comment SO 



PUBLISHED MONTHLY 



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baltimore, md. 



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Entered as second-class matter March 9, 1912, at the post office at Baltimore, Maryland, under the Act of July lfi, 1804 



