Das A U S B L ~ N DER SALZE (The Efflorescence of Salts). Karl groups. At the end of the chapter is to be found (1) a list of Schultze, Hygienic State Institute of Hamburg. First edition. equations, (2) a summary and review, and (3) a list of problems Theodor Steinkopff, Dresden and Leipzig, 1936. ii + 99 pp. and laboratory exercises. The remainder of the cation analysis 36 figs. 15.5 X 23.5 cm. $1.60 net. is treated in a similar manner in Chapters VIII to XI11 inclusive.

This book is by no means a new textbook, but rather a compila- tion of researches which have been made upon the subject of efflorescence. The author has done an excellent piece of work in including so much accurate material within a relatively small number of pages. While the publication is of an introductory character, the material therein constitutes a comprehensive survey of efflorescence and its many applications.

The volume is divided into seven topical divisions as follows: 1. Variety of Names and Early Writings 2. Efflorescence in Soils 3. Climate and Micro-climate 4. Efflorescence of Building Materials 5. Researches Directed toward an Understanding of the

Mechanism of Efflorescence 6. Capillary Theory of Efflorescence 7. Influence of Dispersion

In the book the author discusses in meticulous detail the various aspects of the subject and hrings the available information relative to efflorescence up to date. To supplement the theoretical discussion, the publication is adequately illustrated with both line drawings and photographs, all of which are carefully and accurately made. Throughout the volume, careful attention is given to the continuity of reference material.

In the opinion of the reviewer, the author has succeeded very well in his attempt to treat the subject of efflorescence in a com- prehensive manner. I t is recognized, of course, that it is not possible to treat every phase of the subject in equal detail within such a comparatively small number of pages. The author, therefore, deserves credit for the line publication.

As previously stated, the book is not intended for use as a text, but rather as a source of reference material for anyone engaged upon a piece of research which may involve efflorescent materials and their behavior. The completeness of references is deserving of mention inasmuch ds there is a total of one hundred sixty-three references tabulated at the end of the descriptive material. Their selection shows a wide acquaintance with the prevailing literature on the part of the author.

From the standpoint of chemical education, the reviewer wishes to compliment the author and commend the volume to the attention of the research worker.

R. K. CARLETON RAODB ISLANO STAT= COLEDE KINQSTON. R ~ O D B ISLAND

FUNDAMENTALS OF QUAL.ITAIIVE CHEMICAL ANALYSIS. Roy K. McAlpine, Ph.D., and Byron A. Soule, 2c.D.. University of Michigan. D. Van Nostrand Company, Inc., New York City, 1936. ix + 325 pp. 3 figures and 12 tables. 15 X 23 cm. 52.40 net.

This unusudly well written book is suitable for the second- semester course in college chemistry in which qualitative analysis is presented. In Chapter I is presented some timely review mate- rial which indudes a list of simply stated definitions. Chapters 11, 111, and N treat the topics Chemical Arithme&c, Formulas and Equations, and Ionization Theory in Analytical Processes, respectively. In Chapter V are described in detail several im- portant laboratory manipulations, vie., precipitation, addition of a reagent, folding and fitting a filter paper, filling funnel stem with water, washing precipitates, and removing precipitates from Bter paper. Also, directions far several preliminary ex- periments are given.

Chapteq VI treats the lead, silver, mercury (011s) group. First, common compounds and reactions are described. Second, the precipitation of the group is described. Third, directions for the separation and identification of the cations of the group are given. Next follows a critical review of cousideration~inv~lved in evaluating observations made and the proper use of these observations in reporting the group. This is followed by an excellent discussion on the relation of the group to other cation

The treatment should he valuable to both the student and instructor. What is ordinarily cation group 111 is divided into two parts, the first part including iron, chromium, and aluminum and being designated as group 111, and the second part including zinc. maneanese. cobalt. and nickel. and beine desi-ted as ~ . . ~ ~~~~

group IY. It would seem more convenient to desigmate these two groups as Illa and I I l b The meatest deviation from usu4 practice is a separate rrcatment of thc arsenic, antimony, and tin group, which may be omitted or included as desired.

Chapters X N and XV treat the identification of some simple acid radicals. This treatment is inadequate for more than the simplest cases, which are apparently all that the authors have intended should be included. Chapters XVI and XVII take up the analysis of dry unknowns and appear to be only moderately well done.

In the cases of several of the cations with which the student frequently has dif6culty several good tests are given, e. g.. bis- muth, arsenic, and manganese. Under the tests for manganese is included the oxidation of manganese by periodate, which so far as the reviewer knows has not previously been included in a hook on elementary qualitative analysis. On the whole this bwk is unusnallv well done and should find a wide usefulness.

CHEMICAL DlscovEn~ AND INVENT~ON IN TA6 % N T T R T ~ -~ ---- ~ -- --- CENTURY. Sir Wil2iam A. Tildes. D.Sc., LL.D.. 2c.D. F.R.S. Revised by S. Glasstone, D.Sc., Ph.D.. F.I.C., Lecturer in Chemistry, University of Sheffield. E. P. Dutton & Cam- paw. Inc.. New York City, 1936. Sixthedition,revised and reset. xvi + 4 9 2 ~ ~ . 13.6 X 21.4 cm. 12 portraitsand 131 other illustrations. Price $4.00.

For nearly twenty years this book, the first edition of which appeared in 1917, has made chemistry interesting, and its ac- complishments significant and comprehensible to a large public untrained in the mysteries of the science. The same public since 1917 has been offered many other works of popularization, but the present book remains one of the best of them. While one may reasonably have doubted in 1917 whether the chemical discovery and invention of the seventeen years just past were sueiciently important, sufficiently meren t from the chemical discovery and invention of the nineteenth century, to deserve a new and stout book about them-there ,mn'now, twenty years later, no longer be any doubt that the twentieth century deserves a hook for itself. A revolution has occurred in physics; new foundations, laid largely since 1900, have been accepted and a new structure of chemistry has been erected upon them; new products of organic synthesis have come into common use; vitamins and hormones are discussed in the ,&ily newspapers. The book treats both of the theoretical background and of the practical achievements of contemporary chemistry.

The hook is divided into four sections. The first deals with chemical laboratories and the work which is done in them; the second with modem discoveries and theories, the principleo of chemistry, the electric discharge in gases. the elements of the chemist, the discovery and properties of radium, the structure and disintegration of atoms, solutions, electrolysis. the architec- ture of molecules, catalysis, and colloids; t h e third with modern applications of chemistry, hydrogen, oxygen, nitrogen, the metals and some of their compounds, luminosity of &+mes, petrol, coal tar, the production of dyes, drugs, hormones, and vitamins, perfumes and essential oils, vegetable fiber and cellulose, rubber and plastics, explosives, and the fixation of nitrogen; and the fourth part with modern DromesS in oreanic chemietrv. suears. . - >. ~ ~.. -. protcins, natural colors, eni.ymr,, etc. The trt~ntmmt, as might be expected, conforms rather to Rririvh industrial practice than to American, hut the difirrrnms are not rmportant except to the