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NEW BOOKS
Following an admirable introductory lecture on the relation of physics t o chemistry, the following topics are treated: atomic cohesion; electrovalence and covalence; dimensions of covalent links; heats of formation of covalent links; electrical dipole moments; stereochemistry. The material presented is of the greatest interest t o chemists of every persuasion, and it has been treated in a manner which renders it readily understandable even by those who are not familiar with the original sources from which the work is drawn. The book is highly recommended t o all serious students of chemistry. REYNOLD C. FUSON. Die Bedeckungstheorie der Passivitat der Metalle und ihre experimentelle Begrtindung. By W. J. M ~ L L E R 23 . x 16 cm.; 102 pp. Berlin: Verlag Chemie, 1933. Price: paper, 6 marks; bound, 7 marks. The study of anodic behavior, which has been made by W. J. Muller and his pupils a t Vienna over a period of several years, is well-known to all who are interested in the corrosion and passivity of metals. No adequate description of this work exists, other than the large number of experimental papers which have emanated from Muller’s laboratory, so that the present book, which describes all the essential matter in a compact form, will be welcomed. It should be pointed out, however, that the scope of the book is precisely as indicated by the title; that is t o say, it is essentially a monograph devoted t o the author’s own contributions t o the subject, and scant mention is made of other views. The book is in no sense a balanced dissertation on passivity, and much work on anodic phenomena which has been carried out by other investigators, and which definitely has a bearing on Muller’s work, is passed over with a mere reference. After demonstrating Muller’s most striking contribution t o the subject-that anodic passivity is a time phenomenon-the author formulates equations which represent the laws of sideways-growth and thickening of the film, relates these to specific anodic systems, and incidentally uses the results to explain the rectifying action of the aluminum electrode. The book is well illustrated with photomicrographs and diagrams and can b,q commended as a valuable addition t o the literature on passivity. e
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Infra-red Photography. By S. 0. RAWLING. 13 x 19 cm.; x 57 pp. London: Blackie and Son, Limited, 1933. Price: 3s. 6d. The recent introduction of easily handled infra-red plates by the leading manufacturers of photographic materials has rendered possible the application of infra-red photography to long distance and aerial photography, chemical record work, detection of forgery, photomicrography, and spectroscopy. The author has written an admirably clear account of the handling and applications of the new commercial plates. The chapters which deal with the choice of suitable safelights, light filters, lenses, and photographic apparatus should be carefully read by all who use, or intend to use, infra-red photography for any purpose whatever. I n particular it will surprise most photographers t o learn that leather camera bellows and the various woods used in the construction of dark-slides may transmit sufficient infra-red radiation to cause fogging of the sensitive material. The value of the book is enhanced by the inclusion of a number of excellently reproduced photographs. EDWINE. JELLEY.
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