520 
PHILOSOPHICAL SOCIETY OF WASHINGTON. 
that corrasion and deposition could not occur at the same part of a stream 
at the same time. The valley of the Missouri consists of a flood plain 
which has been many times eroded and deposited, and this work of simul¬ 
taneous erosion and deposition of the same material is still going on, not 
merely at different parts of the river, but on opposite sides of it at the 
same point. 
In reply to further remarks by Major Powell, Mr. Ward stated that at 
the season of the year of which he was speaking there were no other 
influences whatever operating to produce the result, as all the streams 
were so nearly dry that only clear alkaline water flowed in them. 
Mr. B. E. Fernow then read a paper entitled Methods Used 
in Determining the Influence of Forests upon Quantity and 
Frequency of Rains. 
324fh Meeting. November 10, 1888. 
The President in the chair. 
Fifty members and guests present. 
The President announced the election * and acceptance of 
membership of Erasmus Darwin Preston. 
In accordance with the resolution presented at the 323d meet¬ 
ing the following gentlemen were appointed to prepare bio¬ 
graphical sketches of members who have died during the year: 
Mr. Wm. B. Taylor, notice of Dr. Peter Parker, died January 
10, 1888. 
Mr. W. H. Dali, notice of Dr. Emil Bessels, died March 30, 
1888. 
Capt. C. O. Boutelle. notice of Mr. Henry F. Walling, died 
April 8, 1888. 
Mr. H. W. Henshaw, notice of Mr. Thomas Hampson, died 
April 22, 1888. 
Prof. Wm. Harkness, notice of Mr. E. B. Elliott, died May 24, 
1888. 
Mr. I. C. Russell, notice of Prof. R. D. Irving, died May 30, 
1888. 
The programme for the evening consisted of a symposium, 
participated in by Messrs. Gannett, Greely, and Fernow, upon 
the question, Do Forests Influence Rainfall? 
