ical performance in following the directions." The methods are, in general, such as are usually covered in elementary analytical work, and the details of the procedures are accurate. I n only one or two cases are there likely t o be any criticisms. For example, the method used in determining non-carbonate hardness of water should be replaced by the better "soda reagent" method. Also the results would better be stated as "parts per million" instead of "parts per 100,000." The weakest feature ahout the book is the absence of modem analytical theory. It does seem that one scarcely has the right to deny a student the real explanation of all the analytical processes, so far as such explanation is possible. Quantitative analysis offers a splendid opportunity t o drive home the value and sipnificance of the wonderful equilibrium relations found in precipitation and solution, in the color changes of indicators, and in axidation-reduction reactions. The reviewer is also a t a loss t o h o w just why the hook is constructed in loose-leaf form. It hardly seems possible t o insert enough extra sheets t o hold the necessary notes. ete. I n general, the book is good and, without a doubt, will give a student good training in beginning quantitative analysis. W. H. CHAPIN Physical Chemistrg and Biophysics for Students of Biology and Medicine. M A ~ STEEL. W Ph.D., Professor of Biological Chemistry. The Long Island College Hospital. John Wiley & Sons, I n c , New York and London, 372 pp. 38 illustrations. 1928. x 15 X 23 cm. Cloth, $4.00 net.
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The author has selected from the large mass of physico-chemical data those which are most closely allied to biological Drocesses. Knowledge of these fundamentals is essential to a better understanding of the physiology of animals and
plants. Although the book is written primarily for the medical student it will be equally serviceable t o students of other hiological sciences. A glance through the table of contents clearly shows the author's care in the selection of subject-matter. Fifty-eight pages of the book are devoted to the nature and structure of matter. Other topics considered are: general properties of matter; energy transformations in living matter; general nature of solutions; water, the greatest solvent; diffusion and osmotic pressure; the nature and behavior of electrolytes in solution; chemical equilibrium and the law of mass action; measurement of hydrogen-ion concentration; the colloidal state of matter; catalysis and velocity of chemical reactions; dynamical physical chemistry of the cell. More space (86 pages) is giwn t o the discussion of colloids than to any of the other topics. Loeb's researches an proteins and the Donnan membrane equilibrium are included in this chapter. Both an author and a subject index are given. The main discussions are developed historically. The student is led almost unconscioudy t o the modern viewpoints by a series of gradual and natural steps. Numerous and lengthy quotations appear in the body of the text. A book thus written has the advantage of placing the responsibility of statements on the authors quoted and in some cases the disadvantage of subjecting the reader to abrupt changes in style. A few defects have been noted. For example, figure 2 could be improved and made t o a w e with its description in the text. The subject of osmotic pressure is always an invitation for an argument especially when a statement (p. 131) like the following is giwn as a fact: "What is determined in the actual measurement of osmotic pressure is the force whereby the solute attempts t o enter the solvent through a semi-permeable membrane." This is the diffusion pressure of the solute. Generally speaking, this confusion of
VOJ. 5. No. 3
RECENTBOOKS
W s i o n pressure and osmotic pressure is quite common. The book mpplas a much-felt need and will prove excecdmgly useful to hrologiwl students. E m S. JOHNSTON The Electronic Theory of ~alehcy. N. V. SmGwrcK, M.A., Sc.D., D.Sc., P.R.S. Oxford University Press, Ameriean 310 Branch, New York, 1927. xii pages. 4 figs. 24 X 16 cm. $5.00.
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The book gives the fullest account yet available of the principles of valency and molecular constitution, based upon the Rutherford-Bohr atom. It attempts to interpret the fundamentals of valency in molecular structure in terms of the . physical concepts of electrons, nuclei, and orbits, without transmessing the physical laws which these physical entities possess. The book, therefore, outlines the theory of the nuclear atom, the Bohr wncept of the hydrogen atom, and the Bohr-Main, Smith-Stoner proposals for the position of orbital electrons in atoms. With this as a foundation it proceeds with the development af the electronic theory of valency, the familiar views of Kossel, Lewis and Langmuir constituting the fundaments1 basis of presentation. To the ideas of electrovalency and co-valency the wncept of co6rdinate valeucy is added. Having discussed the criteria of each, the applicability to Werner's theory of wardination is illustrated in detail. The idea of a coardinate link with one atom or group as donor of electrons and one as acceptor wnstitutes a necessary amplification and extension of Werner's ideas to double salts and to chelate or ring wmpounds in which latter one part of the molecule acts as donor to another part as acceptor. Molecular association in compounds is attributed to wardinate linkages, as also is solvent power, hydrate formation, and solvation. Atomic and molecular magnetism are then treated. followed bv a discussion of the stereochemistry of various elements
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in their compounds. A more detailed discussion of chelate rings is given and a final chapter is devoted to a skeleton outline of a future volume taking up the applicability of these ideas to the individual elements and their compounds. The author has undoubtedly given us a most lucid treatment of the subject and has succeeded in systematizing, with the aid of a few electronic postulates, a vast mass of iuorgsnic chemistry as well as organic. The book should be read by all teachers of chemistry. I t is already being used with success in at least one university (Princeton) as an advanced text for graduate students in inorganic chemistry. HUGHS. TAYLOR
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The Higher Coal-Tar Hydrocarbons. ARTHURERNEST EVEREST.Longmans, Green and Co., Ltd., New York, 1927. 334 pp. 22 X 14 cm. $7.00. xiii
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As pointed out by the author, the field of wal-tar hydrocarbons is far too extensive to be dealt with in such a volume as this and so 111 hydrocarbons up to and including napbth&ne and anthracene have been omitted. The author has collected and presented in a compact wellarranged form the known facts regarding the acenaphthene, fluorene, and phenanthrene groups of hydrocarbons, together with some miscellaneous groups not included under these headings. A great gain in clarity has been attained hy the care taken with the numbering of the various ring complexes. The number of suggestive things pointed out by the author are many and a few may he mentioned here. Speaking of pyrene, BsHlo, the author staks: "Despite the fact that this substance has been known for a considerable timeLaurent obtained it in an impure state in 1837-it has not yet attracted any great amount of attention, nor has it yet received any large technical application. Glaser has pointed out that this hydrocarbon contains a larger percentage
