W. H. BRAGG and W. L. BRAGG. X-rays and the Structure of Crystals. Translated from the 5th English edition by Yu. V. Wulff and E. V. Shpolsky. “Contemporary Problems of Natural Science,” book 40. State Publishing House, Moscow–Leningrad, 1929, 268 pp., price 2 rubles 75 kopecks.

The Braggs’ book is well known to Russian readers from its first edition (1914), published in 1916 in the translation of Prof. Yu. V. Wulff. In the ten years that elapsed between the first and fifth English editions, the field of research inaugurated by the authors’ work expanded extraordinarily, and it is therefore natural that the book required substantial supplementation. Many chapters have been almost completely reworked—chiefly those dealing with the physical foundations of the methods of structural analysis; others have been written anew (Chapter III—The production of X-rays; Chapter XI—The analysis of crystals and atomic forces; Chapter XII—Organic crystals); and only a few have remained unchanged, namely those in which the Braggs’ first original attempts are described.

penetrate deep into the structure of crystals—attempts crowned with such brilliant success and now become classical.

The newly written chapters and the additions made have not, in general, changed the character of the book. In it, as before, there remain collected chiefly only the authors’ own works, presented with extraordinary clarity and at the same time in such a way that the reader is given the opportunity to follow the authors step by step to their very latest conclusions. However, one also senses a desire somewhat to broaden the scope of the exposition. Thus, for example, a new chapter has been introduced, “Analysis of Crystals by the Powder Method,” where the first investigations by the Debye–Scherrer method are described. Taking into account the date of the 5th edition (1924), it is difficult to expect to find in this chapter exhaustive data on the varied applications of this and related methods; but the thought occurs that the editor of the Russian edition (1929) might perhaps have supplied the book with supplements concerning, for example, the structure of alloys, as well as the X-ray picture of plastic deformation of crystalline bodies, thanks to which the book would have been read with still greater interest in broad circles of metallurgists. A certain delay in the appearance of this book is at times felt while reading it: let us note, for example, that the structure of graphite given on page 118 is incorrect; it would not have been superfluous for the editor to supply this passage with a note. The translation of the book is made in good language, and its appearance makes a good impression. The reissue of the book should be considered very timely.

S. Konobeevsky