SCIENCE 



lAUM iSlS 



nsw sskibs 



Vol. XLIH. No. 1098 



Friday, January 14, 1916 



Single Copies. 16 Cts. 

 Annual SnasoRiPTioN, |8.00 



Every Teacher and School Official, and every Parent with the welfare of his 

 Children at heart should read 



STARR 



THE ADOLESCENT PERIOD 



(Published Dec. 14th, 19 IS) 



Jl straightforward, practical and Well developed treatment of an ever important (but much 



neglected) problem. 



It ia the work of an author who understands the physical changes of the 

 youth period, and their psychical interrelations from the standpoint of both scientific 

 investigator and intimate friend of boys and girls. In clear, untechnical style the 

 dangers and difficulties of this period of life are sketched, and practical, reasonable 

 and conservative suggestions are given. Price $1.00, Postpaid. 



TWO OTHER NOTEWORTHY NEW BOOKS 



OSTWALD'S 



COLLOID-CHEMISTRY 



Recognition of Colloids, Theory of Colloids, and Their General Physico- 

 Chemical Properties. By Dr. Wolfgang Ostwald, Privatdozent in the University 

 of Leipzig; First English Edition Translated from Third German Edition by Dr. 

 Martin H. Fischer, Professor of Physiology, Universitj'^ of Cincinnati; Assisted by 

 Dr. Ealph E. Oesper, Dept. of Chemistry, New York University, and Dr. Louis 

 Berman, Staii Physician, Mount Sinai Hospital, New York. 



With Frontispiece and 60 Text Figures. Octavo. Cloth $3.00, Postpaid. 



SCHINEIDER'S 



Bacteriological Methods in Food and Drugs Laboratories 



With Introduction to Micro-analytical Methods. By Albert Schneider, M.D., 

 Ph.D., Professor of Pharmacognosy and Bacteriology, College of Pharmacy, 

 University of California. With 87 Illustrations and 6 Full Page Plates. Octavo. 

 Cloth $2.50, Postpaid. 



P. BLAKISTON'S SON & CO., PUBLISHERS 



1012 WALNUT STREET PHILADELPHIA, PA. 



