described, several pages being devoted to the daily routine of its dass-mm and laboratory management. Qualitative analysis is the theme of the find chapter in which some advice is given as to the installation of such a course, the preparation of reagents, the use of the author's manual, the dispensing of unknowns, and an apparatus list. The reviewer is skeptical of the wisdom of establishing such a course in the first year of high-school chemistry. References to literature include twohundred and fifty citations which refer for the most part to articles in recent journals. A list of reference books that may be purchased for approximately one hundred dollars might well be in the hands of every high-school librarian. The hook is a worthwhile addition to the literature on the training of chemistry teachers and deserves a place on the reference shelves of instructors of such courses. R. M. PARR Modem Edited W. W. 1926. $2.50.
Science and People's Health. by Benjamin C. Gruenberg. Norton & Co., Inc., New York, 250 pp. 14 X 21.5 cm. vi
+
I n an effort to make the public, in general, appreciate the value of science to the health of humanity, Dr. Gruenberg has collected a chapter each from half a dozen authorities in which each one shows how the development of his speciality has reacted to the gaod of mankind. Professor Charles R. Stockard of Cornell University Medical College demonstrates the impartance of heredity and environment in the development of the individual. Professor Hugh S. Taylor of Princeton explains how important body substances, like insulin, have been made in the laboratory. Professor Walter H. Eddy of Columbia shows how the deficiency diseases can he corrected by the right proportions and kind of food. Dr. William A. White of St. Elizabeth's Hospital in
Washington tells of the effects of our complex and trying mnditions of modem life on the delicately adjusted nervous mechanism of the human body. Dr. C. E. A. Window of Yale gives a comprehensive resum6 of what preventive medicine has accomplished. Dr. Haven Emerson, a former public-health official, sums up the experimental work outlined above and shows how the knowledge so acquired works out in application to human problems. It would be hard to beat these names in any book on the subject and Dr. Gruenberg's long experience in teaching and public health work has shown him what most needs to be known in this field. His introductory essay on "Science in a Democracy" shows the danger and damage done by credulity and illustrates the idea by numerous cases of popular fallacies such as the recent craze for Ahrams' "electronic treatment." E. E. S ~ o s s o ~ Casein, Its Preparation, Chemistry and Technical Utilization. E. L. TAG-, Ph.D., Assmiate Professor of Chemistry, Kansas State Agricultural College. D. Van Nostrand Co., New York City. 1926. v 218 pp. 13 X 20 an. 8.00 net.
+
In the preface the author states: "It is the purpose of this hook to explain the them& and industrial us& of casein in the light of present day practice." and the chapters are as follows:
1. General Cansiderations and Preparation of Pure Casein. 2. Chemistry of Casein. 3. Compounds of Casein with Alkalies and Alkaline Earths. 4. Compounds of Casein with Heavy Metals, etc. 5. Decomposition Products of Casein. 6. Paracasein. 7. Technical Preparation of Casein. 8. Technical Uses of Casein. Patents. Bibliography. Index. The author has accumulated a large
mass of data and arnrnged it as indicated: but there is much in R. Scherer's hook on casein and elsewhere which does not appear here. The 267 references are collected alphabetically a t the end of the hook and thus constitute an author's index. But Dr. Tague's name does not appear a t all and the hook seems to r d e c t this fact. One feels that it contains tw much i$se dixit rather than that type of critical discussion which personal contad with the problems should elicit. Thus, what is the value of "the best empirical formula to date. ClnHar&SPOss" (Harpmersten), when J. B. Leathes points out that in a polypeptid chain of 50 links containing only 19 different kinds of amino acids there are 10" ddierent arrangements possible? What this means may be dimly gauged from the fact that the distance across the Milky Way (an appropriate comparison in the case of casein) expressed in Angstrom units (of which there are 10,000,000 to the mm.), is only "In the preface, it is stated: "A lmze amount of intensive research work must he done before the chemistry of casein will approach a n y t b i i like completeness. Especially is this true of its compounds with other substances. "In as much as casein is a colloid, its behavior can be ex~lainedbest by the principles of colloid chemistry which practice the author has followed throuzhout this book." To the reviewer it appears as if many indefinite adsorption complexes (or, to say the least, indehite compounds of some kind) are given a local habitation and a name, e. g., p. 62, alpha casein, beta casein, iso-casein, easeid, acid and alkali alhuminates, and (p. 46. et sep.) a variety of halogen compounds. In many instances, these are hang-overs from fossil literature but in any event the old German maxim "Papier irl gedultlig" must always he borne in mind. To speak of the chloride of an indefinite compound or substance is somewhat like speaking of the chloride of mince pie.
The author gives (pp. 173-205) ahstracts of some 165 American and foreign patents which he considers mast important and devotes pp. 14Cb172 to practical uses of casein, and pp. 97-140 to the technical preparation of casein. Since only enough HC1 is used technically to bring the Pa to 4.G4.8, it is hard to see why C.P. HCI is recommended or why the precipitating vats should he made of heavily tinned sheet iron. In the next edition, it would be well to epitomize standard methods suggested (e. g.. A. 0. A. C. methods on pp. 13&7), for many who use the book may not have these a t hand. The magnitude of the industry may be seen from the statement that in 1922, about 7,000,000 lbs. of casein were used in the plywood industry in the U. S. A. and enormous amounts are imported from Argentine and France. There are big opportunities for the development of the industry here. The author is to be thanked far tabulating at the outset the existing mess in nomenclature: American English Old French Casebogen= Caseanic Acid Casein Casein Caseogen Paracasein There is much in the book that will prove of interest, yet much to he desired, and the reviewer hopes that the next index will contain "rennin" and "rennet" as well as "smierkase."
* =
=
Jenom ALEXANDER The New Heat Theorem. W. NERNST, translated by Guy Barr from the 2nd German edition. E. P. Duttou and Co., New York, 1926. xvi 281 pp. 13.5 X 21.5 cm. $4.00.
+
First published in 1918, revised by author in 1924 by the addition of notes in a supplement, this work has now been translated into English. It suffers from the long period of time that has elapsed between Erst publication and translation, for the addenda are insu5cient to put the serious student of the subject intb full contact with the present position
