ESTABLISHED IN 1872 



THE POPULAR SCIENCE 

 MONTHLY 



3 DOLLARS A YEAR 25 CENTS A NUMBER 



Edited by Professor J. McKeen Cattell 



The 

 April 



Popular Science Monthly 



Ojjens with an article by Professor \\\ A. Locy, on Malpighi, Swammerdam 

 and Leeuwenhoek, the three men to whom we owe the foundations of biological 

 science. The article is elaborately illustrated with portraits and reproductions 

 from the original works. Mr. Havelock Ellis continues his interesting studies 

 of "British Men of Genius." Professor Paul M. Hanus, of Harvard Univer- 

 sity, discusses two contemporary problems in education, elective studies in 

 schools and the gap between the High school and the lower grades. Professor 

 Edwin G. Dexter, of the University of Illinois, gives statistics showing the 

 influence of the weather on suicide. Professor E. A. Andrews, of Johns 

 Hopkins University, gives in a well illustrated article some curious facts in 

 regard to frogs that care for their young. Mr. Frederick Emory describes the 

 enormous increase in the trade of the United States. Mr. Charles H. Cochrane 

 contributes an article illustrating less known forms of flying machines. Pro- 

 fessor G. N. Stewart, of Western Reserve University, reviews recent i3rogress in 

 physiology, and there are the usual departments devoted to Discussion and 

 Correspondence, Scientific Literature and the Progress of Science. 



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