The American Journal of Science 



Established by Benjamin Silliman in 1818 



The Leading Scientific Journal in the United States 



Devoted to the Physical and Natural Sciences, with special reference to 

 Physics, and Chemistry on the one hand, and to Geology and Mineralogy 



WM. M. DAVIS 



United States 

 ced prices. 



l@r Ten- Volume indexes, Vols. I-X XI-XX, fourth series, priee one dollar. Address 



The American Journal of Science 

 New Haven, Conn. 



University Control 



By J. McKeen Cattell., Professor of Psychology in Columbia University 

 Together with a series of Two Hundred and Ninety-nine Unsigned Letters by Leading Men of Science 

 holding Academic Positions and Articles by Joseph Jastrow, Gbobob T. Ladd, John J. Stevenson, J. E. 

 Crbiohton, J. McKbbn Cattily George M. Stbatton, Stbwabt Paton, John Jat Chapman, Jambs P. 

 Monbob and Jacob Gomj 



helpful way. — Nature. 



d tell ua that a new day is about to dawn in educatioaal writing.— The Boston Evening Transcript. 



science; aine> education 



A series of volumes for the promotion of scienti&c research and educational progress 



VOLUME I. Th< 



Gsohgb Bho-gb Halted of "Science and, Hypothesis." "The Value of 

 I Method." In Press. 



Howell, Franklin P. Mall, Lewbllys F. Barker, Charles S. Minot, 



CotTNCILMAN, THEOBALD SMITH, G. N. STEWABT, C. M. JACKSON, E. P. LTON, 



M. Dodson, C. R. Babdeen, W. OphCls, 8. J. Mbltxer, Jambs Ewino, W. W. 1 



GARRISON, N. Y. 



