JOURNAL O f CHEMICAL EDUCATION
varying through a considerable range, the synthetic products have so oxtended the range of properties as to open up new fields of application. Adequate treatment has been given emulsifable wax, waxy acids. and metallic soaos., as well as to methods for determinine the constants of waxes. Chapter 9 on wax technology serves more to suggest to the reader methods of application of waxes to specific problems than as a cookbook of reoipes and formulas. There is a useful table of physical .constants given in the Appendix. I t is the reviewer's opinion that the interest of the reader would have been served by the inclusion of more data in tabular form, and perhaps by the inclusion of more graphs, line drawings, and flow sheets in place of some of the photographs and the pen and ink drawings.
8. 8. KISTLER
NORTON COYPANT WOBCEBTER, MABBACBDBETTB
Archie G. Worthing a n d David Halliday, respectively, Professor and Assistant Professor of Physics at the University of Pittsburgh. John Wiley and Sons, Ino., New York, 1948. 245 figs. xii 522 pp. 15 X 23 cm. $6.
T m s hook, written by two physicists, "includes material appropriate for s. first undergraduate course to follow an introductory course in physics and for an advanced course for college seniors and early graduate students." Chemists and engineers study much of the material contained in this book in courses in their departments, rather than in physics. Hence, this book is one that will be especially helpful to both student and instructor because of the emphasis given to experimental methods. Too frequently the student knows everything about a particular function, except how it could be determined in the'laboratory. The knowledge of the experimental methods gives a definite basis on which the theoretical ideas can be grounded. Many of the 245 figures illustrate diagrammatically experimental equipment for the subject being discussed. The 13 chapters found in the book are entitled: "Some Laboratory Procedures," "Temperature and Its Measurement," "The Expansivities of Solids and Liquids." "The Dynamical Theory of Heat.," "Calorimetry," "Specific Heats of Solids and Liquids," "Thermal Conduction of Solids and Liquids," "Thermal Properties of Gases," "Elementary Thermodynamics," "Change of Phase," "Heat Engines, Refrigerators, and Human Power Plants." "Conveotion." "Radiant Enerev." The ao-
mathemmttiesl functions. A number of innovations will he found in this hook, all aimed s t clarifying our present indefinite nomenclature. The verb "to mess" has been introduced to apply to the action when the analytical balance is used and 'the verb "to weigh" has been reserved for the use of the spring scales. The abbreviation "pd" is introduced for the mass pound and "lh" is reserved for the force pound. Such exactitude is not always followed, for the authors prefer to define the calory (sic) snd British thermal units in terms of the heat required to raise the temperature of water, &her than use the defined calorie or international steam table B.t.u., both of which are defined in terms of electrical units. Tho reviewer recommends this book to all instructors. whether
chemistry or engineering, whose courses discuss heat and its transformation and thermal properties. Graduate students interested in thermodynamics, and likewise men in industry, will find that this book will clarify many simple but hazy notions v have cancernine" heat and its behavior. that thev " m " KENNETH A . KOBE UNrvEnsnTr OP '
CALCIUM AND PHOSPHORUS IN FOODS AND NUTRITION
Henry C. Sherman, Mitchill Professor Emeritus of Chemistry, Columbia University. Columbia University Press, New York, 1947. vi 176 pp. 12 tables. 7 figs. 14 X 22 cm. $2.75.
CALCIUMand phosphorus are the most abundant mineral elements in the bodies of vertebrate animals. However, human infants are born calcium poor and must increase not only the m o u n t hut also the percentage of cdcium in their bodies to accomplish normal development. A tenfold concentration of the phosphorus content of the environment is called for in development of the vertebrate body. Plants contain their highest concentration of calcium in the leaves, while phosphorus tends to concentrate in the seeds. Cattle, living largely on the leafy parts of plants, may suffer from phosphorous deficiency, and man runs a risk of a ertleium shortage since h~ subsists largely on grains. With this background, the author considers the problems involved in the attainment of nutritional well-heing as it is determinrd by these mineral elements. The book is written from a strictly nutritional point of view and reviews in detail experiments on animals and humans that give data on the levels of intake of calcium and phosphorus that lead to their maximum retention in the growing individual and maintenance in adult life. The thesis that a condition of higher health, well above the merely adequate or passable, may be attained through nutrition is developed, as far as calcium is concerned, by a critical review of the well-known experiments of the author and his collaborators. In these experiments, a diet demonstrated to he adequate through sixty-two generations of rats, when further enriched by calcium led to higher vitality of the animals, especially as shown in breeding records, longer period before onset of senility and increased life expectancy. A chapter is devoted to the food sources of calcium and phosphorus and the influence of foods on the utilization of calcium and phosphorus. The author discusses the state of calcium in the blood and hone and the role of the hone traheculae in helping to maintain the ootimum calcium concentration in the blood. The chemical forms and functions of phosphorus in the body are summarized very briefly. An extensive selected biography of aver 500 titles gives ample references to the reader who desires to pursue in greater detsil and medical aspects of the subjeet. the Short as this book is, the reader will get from it a broad picture of the present knowledge of calcium and phosphorus in animal and human nutrition. He is given a vista of the benefit that may scoruo to the human race rts further understanding is aoquired, not only with respect to the mineral elements, but to other nutritional factors as well. F. A. CAJORI U m v e n s r r ~OF CoLonAoo Bcaaor, oP M l n l a s ~ DENVER. COLORADO