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In the selection of the laboratory exercises, the authors again. Company. ... tone not conducive to the best pedagogical effect. ... enzyme-substrate ...
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RECENT BOOKS QWANTITATI~E ANALYSIS. Harold A . Fales, Ph.D., Professor of Chemistry a t Columbia University, and Frednic Kenny. Ph.D., Professor of Chemistry a t St. Francis College, Brooklyn. Second Edition. D. Appleton-Century Co., Iuc., New York, 1939. xiii 713 pp. 132 figs. 14 X 22 cm. $4.00. I n revising this book, which so successfmlly pioneered the elementary teaching of quantitative analysis from the theoretical viewpoint, the authors have added and interpolated much new and valuable material, without making many appreciable changes in the wording or general organization of the original text. The result is a truly contemporary book, embodying most of the special virtues and some of the defects of the alder edition. The admirable explanatory spirit of the original bas been conserved and even increased, and the reader is often pleased by passages of unusually clear and elegant exposition. In only a few places does one find any marked incoherence or lack of conclusiveness. and the failure to correct such barbarous inventions as "we impliedly know,! (tap page 165) is a defect which seems to be noticeable chiefly because of contrast. I n the selection of the laboratory exercises, the authors again have maintained the policy of the earlier book: some very common determinations (such as the titration of acetic acid) are omitted, but the discussions and explanations are so clear and practical that any fairly intelligent student might well succeed in making his own plansfor such analyses. I n some places, however, one could wish for a larger number of practical examples of the theoretical material; thus the highly detailed and uniquely valuable chapter on electrodeposition is followed by the simple, well-studied example of copper (under various conditions), and a second laboratory example (lead) is found only aft? some searching. In the same spirit the eminently practical chapter on photometric methods contains only one exercise, the Nessler method for ammonia. Most of the chapters dealing with theory have been expanded in the direction of more detail, rather than increasing depth of treatment. Thus the structural formulas of numerous indicators are given exactly as before, without mention of the tautameric forms responsible for the changes of color; the reason for the variation in breadth of color range of different indicators is hinted only very faintly. The reviewer might willingly agree that these are matters of curiosity not closely related to practical analytical work, but the same is true of the formulas themselves. Again. in the discussion of oxidation-reduction equilibria there is a cousiderable tendency toward the use of "bar@ ion formulas, such as Sn++++and Ti++++,instead of the more realistic SnCls- and TiO++, and so forth; here also the difference is not practical, hut the theory lacks precision. I n some few places, the new edition has retained an arbitrary tone not conducive to the best pedagogical effect. The original propaganda against the use of the concept of normality remains in full force, and continues to he effective because of the absence of any clear explanation of ways of avoiding ambiguity. The conventions employed in electrochemistry are traditional, and there is not even a footnote reference to the newer system of Lewis and Randall; inasmuch as this system is used in a t least one of the very best reference books an electrode potentisls, the omission seems unfortunate. I t might he pointed out also that the discussion of oxidation-reduction equilibria is unnecessarily complicated, because of the persistent separation of the electrode potentials throughout every calculation. I t seems that an arrival a t the use of expressions of the form

I n spite of these and other minor defects, this book is far better, both as an elementary texthwk and as a reference-source far more advanced material, than mart of the commonly used textbooks of quantitative analysis. It seems likely that it will be chosen by many careful teachers of the subject. It is one of the very few books, usable for elementary instruction, which gives many references to the original literature; it is almost unique in the use which it makes of ionic activities (although this use is limited, perhaps wisely); it may well be the only textbook of quantitative analysis which includes a really up-to-date summary of the use of organic precipitants. On the whole, it is t o be highly recommended, especially for advanced work, and it should hold a favorable position for a long time to come. ANTONB. BURG TI. U ~ ~ v s a s r ron v Soarnan~C ~ ~ ~ a o n n r A

INORGANIC

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(where ELand E, are the separate electrode potentials and Q is the ionic quotient for the whole reaction) would have simplified the calculations, and also would have given a far clearer picture of the relation to equilibrium constants.

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BIOLOG~CAL OXIDATION.C. Oppenheimer and K. G. Stern, with the collaboration of W . Romma Nordeman Publishing Company. Inc.9 New York 1939. 317 PP. 19 X 26.5 em. $8.25. The book contains the following chapter headings: "Introduction" (five pages); General Part consisting of "Theories of Oxido-Reduction" (forty-eight pages); "Phenomena of Oxidative Catalysis" (seventy-three pages); Special Part consisting of "The Enzyme System" (eleven pages); "General Biological Simificance of Desmolvsis" (thirteen Dazes): . - .. ''Cell Res~iration" (seventeen pages). There is an extensive "Bibliography" (thirty-three pages), and a "Subject Index" but there is no "Author Index." According to the Preface this monograph had been developed from Dr. Oppenheimer's chapter on biological oxidation in his "Suppkment" to "Die Femente." "The text had been made .. less dependent on other expositions. I n doing so it was understwd, however, that for fuller.hfohnation the reader should still be referredYo the 'main work' by Oppenheimer (1926), the Supplement, and to the original publications." I n the first ("General") part of the book the theories dealing with biological oxidations and reductions are excellently dealt with. I n the second ("Special") part, however, there appear a numher of incorrect and confusing statements. The formation of an intermediary erizyme-substrate compound between monoethyl hydrogen peroxide and liver catalase as described by Stern is quoted (page 176). The unstable intermediary compound is supposed to have the properties postulated by the theory of Henry and Michaelis for an intermediary enzyme-substrate compound. Keilin and Hartree (Pmc. Roy. Soc., BlZI, 173 (1936)), however, found that ethylhydrogen peroxide is not a substrate for catalase since weak solutions of ethylhydrogen peroxide are not attacked by catalase solutions if free from other hematin compounds. Doubt is cast (page 207) as to the possibility of obtaining pure synthetic cocarboxylase by the method of Weijlard and Tauber (J. Am. Cham. Soc., 60, 2263 (1938)); whereas it is well known that pure cocarboxylase has been manufactured for some time on n commercial scale by thir proccrc. On page 210 the existence of ascorbic acid oxidarc is qucs~ioned. 1.atrr ,page 2C: one rrads, "The rxwtrnce of ascorbic acid oxidase as a-specific enzyme is more or less generally accepted." The results of course speak for a specific enzyme (Gnauaiuto, Enzymologia. 5, 332 (1939)). The statement (page 267) that only 1-ascorbic acid is attacked by this enzyme is incorrect. dAscorbic acid is also oxidized but at a much slower rate (ROSENBERG, Skand. Arch. Physiol., 76, 119 (1937) and others). I t is stated (page 210) that ascorbic acid is probably the coenzyme of esterase. Pautscheuko-Jurewicz and Kraut (Biochem. Z., 285, 407 (1936)), however, found that ascorbic acid itself cannot be the coenzyme for esterase since on the addition

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