Recent Books Chemical Reactions and Their Equations. INGO W. D. HACKH.P. Blakiston's Son & Co., Philadelphia, Pa., 1928. Sec144 pp. 3 illustraond series. x tions. 12.4 X 18.6 cm. $2.00.
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This book is designed to aid the firstand second-year college students in writing chemical equations and working some of the simple problems based on the equations. It consists of six chapters, an appendix, and glossary. The chapter headings are: Symbols and Elements, Formulas and Compounds, Equations and Reactions Involving No Oxidation and Reduction, Equations and Reactions Involving Oxidation and Reduction, Reactions and Their Control, and Types of Chemical Reactions and Equations. The Appendix consists of (1) Solubility Table. (2) Rules for Salt Formation, (3) Key to All the Eqdations Involving Any Element and Compounds. *The index and glossary defines 99 of the commoner chemical terms. I n general, the author has fulfilled his purpose well. There is an abundance of illustrative equations and an abundance of practice material in the exercises a t the ends of the chapters. The discussion of the periodic system in the first chapter is excellent up t o the last paragraph on "atomic structure." If the student bad sufficient background t o get anything out of this paragraph he would not need so elementary a treatment of the preceding part. The previous elementary treatment is . ~ e r h -a p swhat is needed so this paragraph might just as well be left out. In Chapter I1 we find per cent composition calculated from the formula by means of the old style proportion of dots. This form is perhaps one of the most pernicious causes of confused thinking in all mathematics, and should be completely
abolished; the fractional form of proportion is much less subject t o error. On page 55 are found the terms binary and ternary compounds. These two terms are supertluous t o a knowledge of chemistry and should also be relegated to the trash heap. The student is overwhelmed with necessary terms; why burden him with those that are not needed? Chapter IV on oxidation and reduction should also have been presented from the point of view of gain and loss of electrons. This point of view is gaining in favor. Also there is too much stripping the reactions of the ions and eleme?ts-that are not oxidized and reduced. In practice the student meets the prohlem in terms of complete compounds rather than ions. It will appear that the adverse criticisms are mostly on minor points. I t may then be rightly concluded thet the book on the whole is well gotten up and serves its purpose excellently. 0. L. BRAVER STATE TEACHERS' COLLEGE, SAN JOSE,CALIEORNIA
Annual Survey of American -Chemistry. Volume In. July 1, 1927-July 1. 1928. Edited by CLARENCE J. WEST under the auspices of the Division of Chemistry and Chemical Technology of the National Research Council. Published for the National Research Council by the Chemical Catalog Co., New York, 1928. 395 pp. 13 X 21 cm. $3.00. The ~ublicationof the third volume is a strong confirmation not only of the continued need for such a resume of American research, but also positive evidence of the favorable reception that has been accorded the two previous issues. The present volume contains 46 chapters and 395 pages, which is comparable with the 49 chapters and 415 pages (in-
eluding index) of the preceding survey. The names of 53 well-known chemists appear in the list of authors, 22 of whom assisted in the preparation of Volume 11. The survey in general follows the lines of the preceding issues though, to accommodate additional important fields, the following chapters have been added: Lead; Beryllium in connection with Magnesium; Zinc; Nucleic Acids; Foods; Soils and .Fertilizers; Insecticides; Lime and Gypsum; Gaseous Fuels; Cellulose and Paper; Paint and Varnish. On the other hand, the following subjects found in Volume I1 are omitted,from Volume 111: X-Ray Examination of Materials; Electro-Organic Chemistry; Photochemistry; Inorganic Salts; Common Earths; Microchemistry; Stereochemistry; Copper; Nickel; Proteins; Glass. The reviewer would suggest that chemists could, with profit, read the volume as a whale and not merely the chapters in which they are especially interested. Such a perusal would aid in obtaining a better perspective, which most of us need, of the many fields of chemistry, and to such a reader there areiinteresting items on every page. For instance, one might well imagine the comments as well as astonishment of Berzelius on learning that ethyl lactate can be synthesized, starting from cyanamide by a nitrogen fixation plant a t Niagara Falls. As was said in a previous review, "we owe a debt of gratitude to the research council and the staff of editors for its able and painstaking work in presenting to American chemists this convenient and noteworthy survey of the year's F. B. DAINS literature." OP KANSAS, UNIVERSITY KANSAS LAWKENCE, Introduction to Modem Physics. F. K. R I C H T ~ E RProfessor , of Physics a t Cornell University. First edition. McGraw-Hill Book Co., Inc., New York City, 1928. xv 4- 596 pp. 169 illustrations. 23 X 14.5 cms. $5.00. The purpose of this hook is "to present
such a discussion of the origin, development, and present status of some of the more important concepts of physics, classical as well as modern, a s will give t o the student a correct perspective of the growth and present trend of physics as a whole." I n order to construct the proper hackground and t o develop a fitting perspective for the two great problems in modern physics, (1) the reconciliation of the quantum theory and the wave theory of light, and (2) the structure of matter, the h s t three chapters are devoted t o the historical development of physics as divided into three periods, the earliest period of simple accumulation of data, the period of experimental methods, and the period of "classical" physics. The treatment of the present period of modem physics (since 1887) is concerned with modern developments and the part played .+ry each in determining the theoretical atomic structure of matter. Each phase, such as the photoelectric effect, the quantum theory, series in line spectra, x-rays, the Bohr theory of the atom with its modifications, and radioactivity, is developed briefly from its origin t o its present status. This book should he welcomed as a tent for dass use by advanced students in physics. "The purpose of this book is, frankly, pedagogical," being based on lectures given in a course by the author. For advanced students in chemistry to whom developments in interrelated fields of chemistry and physics are of vital interest, it should serve as an admirable reference, numerous points of contact in the two fields being fully discussed, as illustrated by the chapter on the arrangement of electrons in atoms, dealing with static and dynamic atom models For those with only an elementary knowledge of physics, who, from a cultural or academic point of view, desire to ohtainabird's-eye view of the field of modern physics, this text should prove adequate. In fact, the author has helped meet the long-felt need of presenting in the English language t o the non-specialist in the particular fields discussed, a lucid, understandable, com-
