electron waves for the investigation of organic substances (cellulose, graphites, etc.). On the whole, they give a broad picture, demonstrating the very great significance of this method of structural investigation, which has its own specific features, distinct from those of the X-ray method, and therefore its own specific tasks. A very important and careful study of the features of the electronographic method is needed. It will make it possible to seek out new objects of research for it and to make it a new powerful means of physicochemical analysis.

Several articles are devoted to interesting technical innovations both in the field of X-ray apparatus (Bertold’s article, 10) and with respect to X-ray tubes and methods of structural analysis (2, 10, 11). Among the remaining ones we note Shintzing’s article (9) on the polymorphism of elements and the article by Broily, Gloker, and Kissig (7) on the fine structure of the spectra of chemical compounds.

The first gives a rich survey of the properties and structure of polymorphic elements, establishes close or long-range bonds between them, which should pave the way toward the creation of a complete theory of polymorphic transformations. The article by Broily and Gloker is very brief, so that it hardly touches seriously upon this major question, which is of great importance in the problem of the physical nature of the molecular crystalline bond and has broad prospects for the application of these questions to practical problems of materials science.

Turning now to the question of an overall evaluation of the book and of the desirability of translating it into Russian, one may point out that the book is of unquestionable interest to a wide circle of persons practically engaged in or studying the structural analysis of materials. It may be of no less interest to technologists dealing with materials that are discussed in the above-mentioned articles. However, a Russian edition of the book without revision and additions would hardly be expedient. It must be taken into account that such collections, representing reports on congress papers, always have a character connected with the current moment and are highly liable to become obsolete. Taking into account the long duration of our publishing periods, one must fear that such collections may already be considered obsolete by the time they appear. It is enough to recall the sad experience of translating the first volume. I would consider it expedient to select from the collection a number of articles, perhaps to supplement them with others on analogous questions, and in this form to publish them for our reader. Such a book, subject to the achievements of X-ray analysis in the field of the investigation of organic substances, would be very warmly received both by chemists and by X-ray specialists.

S. T. Konobeevsky

A. ENGEL u. M. STEENBECK — Elektrische Gasentladungen. Ihre Physik u. Technik. Bd. 2 B. Springer. Bd. 2. — Entladungseigenschaften. Technische Anwendungen. 1934. VIII. 352 s., 350 Abb.

A. ENGEL and M. STEENBECK, Electric Discharge in Gases. Physics and Engineering. Vol. I; Types of Discharges. Technical Applications.

The aim of Engel and Steenbeck’s book is to present, in as simple and as clear a form as possible, the complex phenomena of gas discharge and to describe the varied technical applications of these phenomena. The “elementary processes” in a gas discharge are set forth and analyzed in detail in the first volume of the book, which appeared two years ago. The second volume contains a description and theory of the principal types of discharge and of their technical applications.

Since the theory of any type of discharge is based on an analysis of the elementary processes occurring in it, the two volumes of the book constitute an inseparable whole. In keeping with the general orientation of the entire book, the exposition differs greatly from the monographs on gas discharge that are available (Seeliger, Darrow, Thomson). In every question the authors

they strive to give something complete, as far as possible avoiding the large number of controversial questions existing in the field of gas discharge. Therefore Engel and Steenbeck’s book is a very useful textbook for all persons studying discharge phenomena in gases with the aim of clarifying for themselves, in the main, the processes that occur in technical applications of discharge, and of mastering methods of calculating these processes, without going into various details.

This is also aided by the large number of calculation formulas and numerical examples given by the authors. But, of course, for the very same reasons Engel and Steenbeck’s book cannot be regarded as an introductory textbook that would make it possible to embark on research work in this field.

The references to the literature placed at the end of the book help little in this respect: only the paragraphs to which the given, sometimes rather large, list of articles relates are indicated, without further detailing and without any references in the text. The text also does not mention the names of authors or researchers who arrived at a given derivation of the formulas. It is not indicated at all what belongs to the authors’ specific treatment of the question and what has been transferred into the book in its entirety from the ideas and theories of other investigators, what should be considered firmly established and what is still more or less controversial. All this is a shortcoming from the point of view of the interests of the research physicist, but it greatly facilitates the use of the book for the practical engineer and, in this respect, gives it a number of advantages in comparison, for example, with Seeliger’s book Einführung in die Physik der Gasentladungen. The appearance of Engel and Steenbeck’s book in the light in its second volume must be welcomed, owing to this practical bias that distinguishes it from the monographs mentioned above. It must also be emphasized that, in reading the book, one senses the authors’ profound treatment of all the questions touched upon, in accordance with the aims they set themselves.

Turning to the details of the book’s content, we point out that in the first chapter, “Stationary Discharges,” the following are analyzed in detail: the independent (dark and corona) discharge, the glow discharge, and the arc discharge. It is regrettable that high-frequency discharges are touched upon only in passing and that nothing is said about their technical applications. On the other hand, in § 65 the discharge with a hot cathode is analyzed much more fully than in other monographs. In §§ 14–16 the “probe theory” is clearly and quite fully presented. It is advantageous to draw attention to the comparison of the potential distributions of the probe and of the plasma surrounding it with the “contact” potential difference.

A major omission must be considered the absence in §§ 19–21 of a treatment of “ionization growth” and of Rogowski’s simplified, very lucid theory, which is fully in accord with the general character of the book. In the exposition of the glow discharge, rather little space is given to the practically important phenomenon of cathode sputtering (§ 49). The mechanism of the glow discharge is set forth thoughtfully and convincingly (§ 24). Much attention is devoted to the laws of similarity—the exposition is exhaustive. With regard to the arc discharge, the book does not reflect the newest views on the thermal ionization of the gas as a possible mechanism of the arc in some cases. Otherwise, the description and analysis of the arc discharge are carried out as exhaustively as those of the glow discharge.

In the second chapter, “Establishment Processes in Gas Discharges,” §§ 71–76, dealing with the ignition of the discharge and reflecting Steenbeck’s original work to a considerable extent, attract attention.

The “Technical Applications” are allotted pages 198–327. First come not especially fully presented accounts of the ionization chamber, gas-filled photocells, and other applications of a non-self-sustained discharge. The application of discharge gaps for measuring high voltages and the analysis of corona-discharge phenomena on high-voltage lines are presented more fully. Gas purification by discharge is set out in considerable detail.

Next follows a brief description of a number of small applications of the glow discharge: pre-

Bibliography

protectors, lightning-arrester tubes, stabilizers, rectifiers, relays, and oscillographs (Gehrcke tubes) of glow discharge. The section devoted to gas-discharge lamps occupies 16 pages. Here the paucity of those technical details which, evidently, are due to the requirements of industrial secrecy is striking. The processes in a sodium lamp are described more or less in detail. The mercury lamp of intense burning (high pressure) is almost entirely passed over. Twenty-eight pages are devoted to rectifiers of various types. Here the authors are less sparing with drawings and minor technical indications. It is curious that phenomena occurring in thyratrons are set forth in detail in § 104–107, but only from the standpoint of rectifying currents, although all this is fully applicable to thyratrons. The very word “thyratron” is not mentioned anywhere, just as the specific applications of “rectifiers with a control grid” are not described; these are spoken of in the text as thyratrons. The next section (13 pp.) deals with the “arc for electric welding” and, finally, the last (30 pp.) with arresters and fuses.

In conclusion, let us note once again the originality of all the drawings in the second volume, which have been compiled entirely anew, whereas other monographs on gas discharge usually repeat, one after another, figures taken from the fundamental original works in this field.

In general, the book satisfies the task set by the authors, and a prompt translation of the second volume into Russian is highly desirable.

N. Kaptsov

Responsible editor E. V. Shpolsky. Technical editor A. A. Soloveichik.

ONTI No. 75. Index T-T-60. Print run 3,900 + 50 separate impressions. Sent for typesetting 23.V-35. Signed for printing 11.VII-35. Paper format 62 × 94. Printer’s sheets 9.23. Paper sheets 3½. Printed characters per paper sheet 101000. Order No. 859. Authorized by Glavlit B-25502. Released July 1935.

3rd Printing House of ONTI named after Bukharin. Leningrad, Moiseenko St., 10.