VOL. 4. NO. 2 RECENT BOOKS 269

of the average student. This very im- portant fact has been verified in regard to some of the work by one of the re- viewers.

The book should prove a valuable help to dairy departments, municipal milk in- spectors, nutrition departments and all others interested in milk and milk prod- ucts. It fills a lang-felt need for a manual that gives emphasis to the colloidal and biochemical principles underlying the average routine dairy tests.

STATIE ERIKSON R. N. MAXSON

The Preparation and Analysis of Organic Compounds. J. BERNARD COLEMAA- AND FRANCIS ARNALI.. P. Blakiston's Son & Co., Philadelphia, 1926. xvi + 352 pp. 13.5 X 21.5 cm. $4.03.

A book designed to place before the student a course of practical organic chemistry. It differs little in its scope from the usual conventional text-books written for presenting this subject to be- ginners and includes typical processes of laboratory synthesis with general methods of analysis both qualitative and quantita- tive. The series of preparations are quite comprehensive, and described in detail to aid the student. and prefaced with expla- nations regarding the theoretical processes involved. The authors have amanged their preparations in groups of related organic compounds, in this manner avoid- ing the method generally adopted of tak- ing up the preparations in the order of increasing difficulty of application in the laboratory. The authors have intro- duced a scheme of organic analysis, some- what original in conception in an ele- mentary book of this character in which an endeavor has been made to systematize and organize an orderly arrangement of analytical procedure. This is an excellent feature and the method of treatment should be of assistance in stimulating a . greater interest in the subject. Anything that can he done to systematize the sub- ject of organic chemistry should be en-

couraged. Teachers of organic chemistry are somewhat inclined to dace too much emphasis on the question of laboratory preparation in introductory courses and to give too little attention to system and organized technic. Just as important for success, as skill in manipulation or technic and familiarity with laboratory methods of synthesis, is the ability to analyze ac- curately mixtures of organic substances and establish the presence of character. istic groupings and to be able to work with small quantities of material. The im- portance of this is illustrated in the newer fields of biochemistry where we are called upon to carry out very careful chemical diagnosis in order to make progress. The synthesis is the final chemid achieve- ment. The hook serves a good purpose in emphasizing this particular phase of elementary instruction in organic chem- istry.

TRSAT B. JOHNSON

Physical Chemistry for Colleges. E. B. MILLARD, A s ~ c i s t e Professor of Physi- cal Chemistry, Massachusetts Institute of Technology. McGraw-Hill Book Co., Inc., New Yark. Second Edition. ix + 468 pp. 81 figures and 128 tables. 13.5 X 20 cm. $3.50.

The author's purpose, as stated in the preface of the original edition, has been "to bring before college students certain of the more important aspects of physical chemistry, together with accurate modem data which illustrate the applicability of its laws to the phenomena observed in the laboratory."

The second edition involves no funda- mental changes and such changes as have been made are intended to bring certain topics up-to-date and to give a fuller pre- sentation to keep pace with the relative increase in importance of such portions. To give an idea as to what changes this plan of the author has involved there is given below a list of chapter headings to- gether with the increase which the second edition has added to each.

Chap. No. Chap. heading

I Introduction, Determina- tion of Atomic Weights

I1 Laws of Gases 111 Liquid Substances IV Solids V SolutionsIdeal Solutions VI Ionized Solutes. Electrical

Conductance VII Thermochemistry VIII Homogeneous Chemical

Equilibria IX Heterogeneous Chemical

Equilibria X Velocity of Chemical Reac-

tions X I Physical Properties and

Chemical Structure XI1 The Periodic Law XI11 Radiochemistry and Radio-,

adivity XIV Atomic Structure XV Surface Chemistry--Col-

loids XVI Electrochemistry-Electro-

motive Force

NO. pages added

by 2nd ediL tion

0 I a

13 4

6 1

1

3

3

0 0

1 2

7

2

This will serve to give to any one familiar with the first edition an idea of the changes introduced by the semnd edition.

The book is well mitten and its value much increased by the problems added a t the end of nearly every chapter and also by the large amount of well-chosen ex- perimental data taken from the literature.

The reviewer does not see the desira- bility of making such little use in a book

of this kind of such fundamental interpre- tations of chemical reactions as given by the laws of thermodynamics. Because an excellent text-hook an this suhject has appeared does not seem to justify relegat- ing this important subject mostly to foot- notes. The author has assumed that students using this book will have had adequate courses in physics and calculus. I t appears to the reviewer that this subject should have been given more emphasis even a t the expense, if necessary, of re- ducing the attention given to exploiting the more naive conceptions which the ex- perimental data quoted by the author show to be only approximations.

J. C. W. FRAZ~BR