486 
PHILOSOPHICAL SOCIETY OF WASHINGTON. 
4§7th Meeting. March 4, 1899- 
President Tittmann in the chair. 
Twenty-one members and guests present. 
Under the head of informal communications, Mr. Tittmann 
submitted a question as to The condition of meteorological ob¬ 
servations in Puerto Rico. 
Discussed by Mr. Bigelow. 
Mr. Gore called attention to A new determination, by Bak- 
huyzen, of the periodic change of latitude. 
Mr. Bigelow read a review of a paper by Lemstrom on Elec¬ 
tricity and vegetation. [For brief abstract see Science, 1899, 
March 24, new series, vol. ix, no. 221, p. 454.] 
Discussed by Messrs. Briggs, Sternberg, Bell, Wead, and 
Tittmann. 
Mr. Sternberg read a paper entitled Some sanitary lessons in 
the late war. [Published in the Journal of the American Medi¬ 
cal Association, June 10, 1899; also as a separate.] 
Discussed by Messrs. Briggs, Bell, Bigelow, and Tittmann. 
498th Meeting. March 18. 1899. 
President Tittmann in the chair. 
Twenty-six members present. 
A lantern just bought for the use of the Society was exhibited 
and tested. Mr. True, chairman of the purchasing committee, 
made an informal report on the action of his committee. 
There followed a brief discussion of the proposed celebration 
of the 500th meeting. 
Mr. Bigelow made an informal communication on Electric 
farming. [Not published.] 
Mr. Artemas Martin read a paper entitled Triangles whose 
angles are 60° or 120° and sides whole numbers. [This paper 
