Book reviewed in this article:Our Farm World, by Fred T. Ullrich, Director of Agricultural Education, State Teachers' College, Platteville, Wisconsin, xi plusCommunity Hygiene, by Dean Franklin Smiley, Medical Adviser, and Assistant Professor of Hygiene in Cornell University and Adrian Gould, Assistant Medical Adviser, and Assistant Professor of Hygiene in Cornell University, x plusThe Health of Youth, by Florence L. Meredith, Professor of Hygiene, Tufts College, Medford, Mass. xxviii plus 535Economic Biology, by George P. Weldon, Instructor of Biology, Entomology and Pomology, Chaffey Union High School and Junior College, Ontario, California, xi plusPlane and Spherical Trigonometry, by J. Shibli, The Pennsylvania State College. Pages xii+217+93.Plane Trigonometry, by Carl A. Garabedian and Jean Winston, The University of Cincinnati.The Supervision of Secondary Subjects, edited by Willis L. Uhl, Professor of Education and Dean of the School of Education in the University of Washington: Cloth.The Logic of Modern Physics by P. W. Bridgman, Hollis Professor of Mathematics and Natural History, Harvard.Modern Algebra. First Course, by Raleigh Schorling and John R. Clark.Modern Algebra. Second Course, by Raleigh Schorling, John R. Clark, and Selma A. Lindeil.Descriptive Geometry, by Harvey Herbert Jordan and Francis Marion Porter, The University of Illinois.A History of Mathematical Notations, by Florian Cajori, Ph. D., Professor of the History of Mathematics, University of California.Identification and Properties of the Common Metals and Non‐Metals, by J. E. Belcher and J. C. Colbert, Assistant Professors of Chemistry in the University of Oklahoma. First editio