NEW BOOKS
397
The Physical Properties of Colloidal Solutions. By E. F. BURTON.23 x 16 cm.; 235 pp. London: Longmans, Green and Co., 1938. Price: 15s. Od. net. viii
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The new edition of this well-known textbook has been very largely rewritten and much new material introduced. As in previous editions the historical method of approach has been employed to great advantage, and numerous verbatim extracts from papers of historical importance have been most skillfully introduced into the text. The treatment of the Brownian movement, particle distribution, and fluctuations is much more complete than is usually found In a textbook of this type, while the chapter summarizing the various available methods for the determination of Avogadro’s number, emphasizing, in a quotation from W. Ostwald, that the concordance of the results provides one of the strongest proofs of the objective reality of the atomic hypothesis, is specially interesting. While one feels at times that the author’s own conclusions are sometimes given undue emphasis-the “conspiracy of opposition” (page 100) is perhaps not entirely wanton-the attitude adopted is certainly preferable to any colorless attempt a t complete impartiality. The chapter on electrokinetic phenomena, and to a less extent that on coagulation, have an “old-fashioned” flavor, and are, in the reviewer’s opinion, not of the same standard as the earlier parts of the book. The transport method of electrophoretic investigation is ignored, as also are important investigations into the theory of the moving boundary method. The frequently observed unequal motion of the two boundaries is provisionally attributed to “settling” and is said (page 175) t o be immaterial provided the mean is taken; in fact the Kohlrausch-Weber theory shows that i t is an intrinsic phenomenon and that the mean is not the correct value. The difficulties arising from inhomogeneity of the potential gradient are dismissed too summarily. Figure 33 (c) is misleading, as the flow distribution drawn is not that given by equation 31, and no mention is made of the fact that, with a cell of the dimensions shown in figure 33 (a), this equation would itself be many per cent in error. While numerous similar points of criticism can be found, the fact remains that the book is stimulating and informative; it is a book to read. D. C. HENRY.
International Annual Tables of Constants and Numerical Data. Vol. XI, Part I (1931-34)and additional separate monographs of Volumes X I and XII. Published under the auspices of the International Council of Scientific Unions and of the International Union of Chemistry. Paris, France: Hermann et Cie. Price: Vol. XI, Part I, 290 francs. Volume XI, Part I, of these annual tables contains twenty-five sections covering the following subjects for the years 1931-34: 1. General Indications. 2. Universal Constants. 3. Elasticity, Compressibility. 4. Thermal Expansion. 5. Density. 6, Viscosity. 7. Surface Tension. 8. Heat Conductivity. 9. Specific Heat. 10. Free Energy, Heat Content, Entropy. 11.Activity. 12. Thermochemistry, Calorimetry. 13. Vapor Pressure, Boiling Temperatures. 14. Gas Laws. 15. Acoustics. 16. Diffusion, Osmosis. 17. Volta Effect, Triboelectricity. 18. Thermoelectricity. 19. Piezoelectricity. 20. Metallic Electrical Conductivity. 21. Supraconductivity. 22. Dielectric Constants, Dipole Moments. 23. Paramagnetism, Diamagnetism. 24. Ferromagnetism. 25. Hall Effect. Section 26, Raman Effect, and section 26, Rotatory Power, appeared as separate monographs. Volume XII, Part I, covering all of these subjects for the years 1935-36 will appear
