I 
536 PHILOSOPHICAL SOCIETY OF WASHINGTON. 
Mr. T. Nelson Dale, by invitation, presented a communication 
entitled A few words on the geology of eastern New York. [Not 
published. This communication was an abridged account of 
the matter published in Monographs of the U. S. Geological 
Survey, volume 23. 4°, Washington, 1894, pp. 119-206; and 
in the Thirteenth Annual Report of the U. S. Geological Survey. 
8°, Washington, 1893, part 2, pp. 291-340.] 
This was discussed by Messrs. Van Hise, Gilbert, and Dale. 
420th Meeting. April 14, 1894. 
President Fletcher in the chair. 
Forty members and guests present. 
Mr. W J McGee read a paper on The antiquity of man in 
America. [Printed (in part) in the Epitome. 8°, Washington, 
1894, vol. 1, pp. 1-8.] 
Remarks were made by Messrs. Harkness and McGee. 
Mr. Albrecht Wirth, by invitation, made a communication 
on Some modern African problems. 
Remarks were made by Messrs. Adler and Wirth. 
421st Meeting. April 28, 1894. 
President Fletcher in the chair. 
Nineteen members present. 
Mr. E. D. Preston read a paper entitled Mean density of the 
earth from two Hawaiian mountains. [Published in this vol¬ 
ume, pp. 369-396.] 
This was discussed by Messrs. Harkness, Farquhar, and 
Preston. 
Mr. Cleveland Abbe presented a paper on The continental 
deficit of gravity and its meteorological bearings. [Published in 
