Established in i8'/2. 



THE POPULAR SCIENCE 



3 DOLLARS 

 A YEAR 



MONTHLY 



Edited by 

 Professor J. McKeerv Cattell 



25 CENTS 

 A NUMBER 



THE POPULAR SCIENCE MONTHLY for May contains a series of articles of interest not 

 only to students of science, but to all readers who wish to keep informed of scientific progress, even though 

 they may have no special scientific knowledge. The number opens with an article by Dr. W. J. 

 Holland, Director of the Carnegie Museum at Pittsburg, describing the institudon which Mr. Carnegie 

 has so liberally endowed, and which it is said he intends to make the greatest institution of its character 

 in the world. The article is fully illustrated, and includes plans for the enlargement made possible by 

 Mr. Carnegie's recent gift of ^3,000,000. President David Starr Jordan, of the Leland Stanford Jr. 

 University, contributes an article entitled "The Blood of the Nation," in which, as a student of the 

 theory of biological evolution, he points out the causes which lead to national efliciency and to degenera- 

 don by the survival of the unfit. Dr. Frederick A. Cook, one of the members of the Antarctic Expe- 

 dition that penetrated furthest south, describes the auroras of the southern sky, which have never before 

 been portrayed and illustrated. Professor R. H. Thurston, Director of Sibley College, Cornell Univer- 

 sity, contributes an article on the progress and tendency of mechanical engineering during the nineteenth 

 century, a subject of very general interest treated by the most competent authority in America. Brother 

 Potamain, Professor of Physics in Manhattan College, gives an account of Gilbert of Colchester, the 

 founder of modern magnetism and electricity, the tercentenary of whose death is being celebrated this 

 year. Professor E. A. Andrews, of the Johns Hopkins University, in an illustrated article describes 

 many interesting and curious facts regarding frogs that take care of their young. Mr. Haveiock Ellis, 

 Editor of the Contemporary Science Series, continues his study of British genius, the present article being 

 devoted to childhood, youth and education. The number, as usual, contains short contributions, giving 

 the most rece.it information regarding scientific literature and scientific progress. 



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