Vol. VI No. 2 



January 19, 1916 



JOURNAL 



OF THE 



WASHINGTON ACADEMY 



OF SCIENCES 



BOARD OF EDITORS 

 Fred. E. Wright William R. Maxon' Edson S. Bastin 



GEOPHYSICAL LABORATORY NATIONAL MUSEUM GEOLOGICAL SURVEY 



PUBLISHED SEMI-MONTHLY 

 EXCEPT IN JULY, AUGUST, AND SEPTEMBER, WHEN MONTHLY 



BY THE 



WASHINGTON ACADEMY OF SCIENCES 



OFFICE OF PUBLICATION 



WILLIAMS & WILKINS CO. 



BALTIMORE, MD. 



Entered as second-class matter July 14, 1911, at the post office at Baltimore, Maryland, under the Act of 



July 16, 1894 



