RECENT BOOKS

SEMIMICRO Q ~ A L ~ T A T ~ V E ANALYSIS OR INORGANIC MATEFZALS. W. B. Meldrum, Professor of Chemistry, Haverford College; E. W. Flosdorf, Assistant Professor of Bacteriology, University of Pennsylvania; and A. F. Dnggctt, Assistant Professor of Chemistry. University of New Hampshire. American Book Company, New York City, 1939. xiv + 354 pp. 22 figs. 14 X 22 cm. $2.75. Texts of qualitative analysis have been appearing in such

quick succession that the interest of chemistry teachers and of chemists in general can be aroused only when some definitely new features, methods or points of view are presented. This was certainly the case with the QUALITATIVE ANn~ysrs OP INORGANIC MATERIALS by the lirst two of the pment three authors, a book which has been reported on by another reviewer in the December, 1938, issue of THIS J o m & and the main feature of which was a new systematic analysis of the anions. The mano methods expounded in the previous bwk are now transformed into semi- mino methods without any change in their chemistry. Quan- tities of materials are usually one-tenth or less of their values in the macro methods. Precipitations are carried out in 3-ml. conical centrifuge tubes. Separations are accomplished in a centrifuge of 1.500 R.P.M., the supernatant liquid being removed by means of a dropper pipet. The whole technic of semimicro manipulations is presented in four pages (pages 170-3).

Large portions of the two bwks are identical word for word. Part I, devoted to Fundamental Principles, now occupies one hundred fifty-seven pages instead of eighty-six and can be re- garded as a sound and satisfactory account of the elements of the physical chemistry of solutions. Several additions to the previous text are welcome, for instance the paragraph on hydroxide complex ions (pages 1324). We would have liked to see the authors use the evidence in favor of these ions (Zn- ~- -~~ ~-~ ~ ~~~~~~ - ~ ~

(OH),- for H%nOt-, and so forth) instead of leaving the ma'tter undecided. We fail, moreover, to see why only the formulas of the HZnOt- type correspond to the amphoteric behavior of Zn(OH),, since the two equilibria

Zn++ + 20H- * Zn(OH), = H+ + HZnOr-

can, in the new interpretation, be written as

Zn(ItO),++ + 20H- $ Zn(OH)n + 4Hz0 *20HsC + Zn(OH).-

Part 11, devoted to Laboratory Work, occu$ies one hundred seventeen pages instead of one hundred fourteen, but the Re- actions of the Ions, previously included in this section, are now more clearly presented in a separate section of farty-three pages. The Appendix is largely similar to that of the previous hook. A useful addition is a list of references for special reagents (pages 3424).

I t is interesting to note that all the methods and particularly the new analysis of the anions have been thoroughly and satis- factorily tested in their semimicro form in the classes of one of the authors. Repeated testing of this type is highly desirable in order to regulate and guidethe trend toward the general use of semimicro methods in elementary college courses.

P I E ~ E VAN RYSSELBERGAE Srnmoao Uxrvsasm

Smsro~o U-m.slru. CALlaoaaU

DAS CH~MISCWE FEUERL~~SCHWBSEN. Dr. 01kW K Q U S C ~ . Volume21 of theSeries CWEMIE m n TECHN~KDER GEGENWAUT edited by Dr. H. Carlsohn. Professor a t the University of Leipzig. S. Hirzel, Leipzig, 1939. xi + 283 pp. 89 figs. 15 X 25 em. Paper cover, R.M. 17; cloth bound R.M. 18.50 ($5.35, plus postage. New York City). The manufacture, storage, and industrial, as well as domestic

applications of the large variety of intlammable solids, liquids. and eases used todav has increased areatly the fire hazard in

homes and industry and has made it necessary to devise con- stantly new and more efficient means of fighting fires from these new as well as old hazards. Although water is still employed today, the use of chemicals of various types has been of great aid to the modern fire fighter in his never-ending struggle against this destructive force. It has been the object of this hook to describe all these methods in which chemical compounds or elements are used, either directly or indirectly after chemical transformation, to combat fires. I n this attempt the author has been remarkably successful. The parts played by solids, liquids, gases, vapors, and chemical foam as well as the more recent development known as air foam (sometimes called mechani- cal foam) in our modem methods of lire extinguishment, are discussed fully in different chapters from the beginning of their use up to the present time. The German and foreign scientific and patent literature is considered in detail, and modern commer- cial fire extinguishers and lire fighting installations marketed in Germany are shown in many illustrations. Various types of fire extinguishers approved for use in Germany by the "Feuer- wehrbeirat" are listed in tables. Following the descriptive section of the baok there is given a patent index, a list of paten- tees, literature references, a list of important fire hazards, and a subject index.

Although this hwk was evidently written principally for use in Germany, the American reader will obtain from it an excellent description of the use of chemicals in our current firedghting operations. However, he will lcuk in vain for information con- cerning American methods and American applications of the chemical facts discussed. American extinguishers and fire- fighting installations are neither described nor shown, in spite of the fact that research laboratories of various American manufac- turers are constantly making contributions to the science of fire fighting. Likewise the part played by such organizations as the Underwriters' Laboratories, Inc., the Inspection Department of the Associated F&tory Mutual Fire Insurance Companies. The National Bureau of Standards in Washington. D. C., and others in the establishment of minimum standards far modern fire protection is not described.

The format of the baok has been well chosen. The printing is gwd and the clear, distinctive illustcations are quite satis- factory. The reviewer found only a very few typographical errors of minor significance. It would be helpful if in subsequent editions the year of issue he given for each patent cited.

LEG POL^ ScmaLna PY~BNB M A N ~ A C T O ~ N O COWPINY

N s a A m . Nsw Jeasiiv

TnsRanoouNmrcs nm, CHEMISTRY. F. H. MacDougnll, M.A. PLD.. Professor of Physical Chemistry. University of Min- nesota. Third Edition. John Wiley & Sons, Inc., New York City, 1939. ix + 491 pp. 53 figs. 15 X 23 cm. $5.00. Those who are familiar with earlier editions of this book

will find the third edition practically an independent work. I t has been almost entirely rewritten and enlarged about twenty- five per cent.. yet the excellence of style, order, and so forth, has been retained. Professor MacDougall has succeeded in giving life and warmth to the ordinarily cold abstractions of thermodynamics. The purist will be disturbed by the inclusion of such extra-thermodynamic subjects as Debye-Huckel theory and quantum and statistical mechanics, but the value and in- terest of the book is undoubtedly Mhanced thereby. These subjects, as well as heat, fugacity, activity and activity coeffi- cients, electromotive force and electrical potential, have been discussed very much more extensively. Entirely new are chap- ters on mathematical procedures and the thermodynamics of gravitational, centrifugal. and electrical fields and surface tension. New also is the statistical interpretation of entropy Unusual