THE 



POPULAR SCIENCE 

 MONTHLY 



Established in 1872 by Messrs. D. Appleton 

 and Company, and Dr. E. L. Youmans. 



The Popular Science Monthly will hereafter be published by 

 Messrs. McClure, Phillips and Company, New York, and edited by 

 Prof. J. McKeen Cattell, of Columbia University, with the assistance 

 of Dr. E. L. Thorndike, also of Columbia University. 



The fifty-six volumes of the journal already published have per- 

 formed an important service for the' advancement and diffusion of 

 knowledge. Its issues have each month carried to all parts of the 

 country reliable information in regard to the advances of science, widen- 

 ing and deepening everywhere an intelligent interest in scientific sub- 

 jects. The journal represented the doctrine of evolution before its 

 tenets were generally accepted; it has done much to diffuse knowledge 

 of physical science and of the applications of science; it has been a 

 factor in the development which has reformed our entire educational 

 system from the kindergarten to the university; its contributors have 

 included many of the world's greatest men of science. 



In the future, as in the past, The Popular Science Monthly 

 will aim to represent fully and accurately the advance of science; it 

 will permit the leading men of science to bring their work before the 

 largest public; it will set a standard to the popular press in its treatment 

 of scientific topics; it will secure the general interest in science that is 

 needed for its adequate recognition and support. 



A journal with these aims is essential, both to men of science and 

 to the general public. It brings men of science into contact with those 

 whose sympathy and help they need, while it enables the general public 

 to follow intelligently the progress of science and its contributions to 

 civilization. This double service of The Popular Science Monthly 

 is fully recognized ; it has the largest circulation of any scientific journal 

 in the world, and it will be conducted with the support of the leading 

 men of science, including in America: 



Cleveland Abbe, Professor of Meteorology, United States Weather Bureau. 

 Cyrus Adler, Librarian, Smithsonian Institution. 

 Edward Atkinson, Boston. * 



W. O. Atwater, Professor of Chemistry, Wesleyan University. 

 J. A. Allen, Curator of Vertebrate Zoology, American Museum of Natural His- 

 tory. 

 L. H. Bailey, Professor of Horticulture, Cornell University. 

 Marcus Baker, United States Geological Survey. 

 J. Mark Baldwin, Professor of Psychology, Princeton University. 



