it cannot be expounded in 50 pages with sufficient completeness. A reader unfamiliar with the special literature will experience difficulties in reading this part. For a specialist, however, it is invaluable by virtue of its brevity. On the other hand, the last section of the book, occupying the second half and devoted to experimental materials on the passage of electron rays through matter, is very substantial and successfully presented. A worker in a laboratory for electron analysis of materials will find in this section answers to many questions arising in his everyday work. Experiments on the scattering of electrons by individual particles, by crystals, and, finally, questions connected with the dissociation of molecules after impact by electrons are described in detail.

The large number of photographs, tables, and curves makes this part of the book very valuable. Since the practical use of electron rays is acquiring ever greater importance among us with each passing year, one can only wish for the appearance of this useful book in Russian translation.

Yu. Rumer

ARTHUR EDDINGTON, Prof., New Pathways in Science. Messenger lectures. L., Cambr., Univ. Pr., 1935, X, 333, 1 p., Sh. 10, 6.

ARTHUR EDDINGTON, New Pathways in Science.

Eddington’s books, devoted to a profound analysis and bold generalizations of modern physics, are always of great interest. Like Jeans, Eddington possesses that scientific pathos and flight of thought which make his books fascinating and awaken in the reader admiration for the power of the human mind and the successes of modern science. He is not a dry scholar who can set forth his thoughts only before a narrow circle of specialists, but is able to find words and images accessible to a broad audience. His latest book is, in this respect, most successful. In it he sets out his scientific and philosophical credo and defends it with all the passion of a convinced man.

Eddington stands wholly on the position of philosophical idealism, which is hostile to us. Since Eddington reflects views that have great influence on the physical thought of the West, his views deserve serious examination in our philosophical literature. One must hope that one of our Marxist physicists, standing at the height of the contemporary development of science, will take on this work. Eddington’s philosophical views are set forth in the first chapter of the book under review. It is curious that Eddington’s views meet, it is true, with weak, but still with some resistance from various thinkers who, on the whole, stand on Eddington’s positions. He devotes the last chapter of his book to an analysis of discussions with his opponents.

Beginning with the second chapter, Eddington gives, in broad, vivid strokes, a picture of contemporary views on the nature of matter. His images are bright and easily remembered. The language is rich and lively, and the reading of these sections of the book gives deep satisfaction. Approaching questions about the ether, Eddington’s experiment demonstrates its equivocal position. He recognizes that all attempts of the past century to establish the mechanical properties of the ether (its density, elasticity, discrete structure, etc.) have not been crowned with success. Instead of drawing from this the single correct conclusion that the conception of the ether is only an auxiliary means of describing phenomena connected with real matter, a means useful only at a certain stage for a phenomenological picture, Eddington goes so far as to agree that the ether is not material at all, and that the concepts of ether, space, and field are identical concepts, having only three words for their expression.

In the following chapters there is an exposition of the contemporary physical theories connected with quantum physics and the crisis of determinism. Here too Eddington openly takes a point of view hostile to us, endowing the electron with the miraculous properties of knowing what the neighboring electron intends to do.

BIBLIOGRAPHY

The chapters devoted to the interior of stars, subatomic energy, stellar nebulae, and the expanding universe are the most brilliant and interesting. Eddington—the philosopher of modest powers—without noticing it himself, recedes into the background. Having left behind his philosophical wanderings, the inquisitive scholar applies the full force of his talent to a brilliant exposition of modern science. In this he is an exceptional master. Even a specialist will learn much from these chapters and will clarify for himself much that he had not previously considered.

The final chapters on world constants and group theory present an exposition of Eddington’s basic ideas, to the development of which, as he himself writes, he devoted the last six years.

Eddington is a modern Pythagorean. Armed with all the knowledge of the day, Eddington does not lose hope of finding in the relations among the world constants the key to understanding the unsolved problems of contemporary physics. He is especially interested in the connection between macroscopic constants, which determine the structure of the universe, and microscopic ones, which determine the structure of the electron. Wherever possible, he returns to the theme of the connection between cosmology, the general theory of relativity, and the concepts of quantum mechanics.

The scholarly world is skeptical toward Eddington’s almost magical investigations. It is difficult to suppose that scientific progress is to be expected in this area.

For our reader, Eddington’s book is not suitable. In the hands of an experienced editor, however, the book could be made very useful. If its length were reduced to one third and the philosophy of no value were thrown out, the book could bring enormous benefit to our reader, who is truly hungry for high-quality popular literature.

Yu. Rumer

NEWLY PUBLISHED BOOKS*

Mechanics

G. LAMB, Theoretical Mechanics, vol. II. ONTI, State Theoretical Publishing House, M.—L., 1933.

Vol. II. Dynamics, translated from the English by V. M. Abramov and N. T. Shvekovsky, edited by Prof. A. I. Nekrasov, 331 pp. with drawings, 5,000 copies, 4 rubles + 1 ruble binding. On the reverse of the title page—the original in English.

Contents. Kinematics and dynamics of rectilinear motion. Kinematics of plane motion. Dynamics of a point in a plane: Cartesian coordinates. Tangential and normal acceleration. Unconstrained motion. Motion of a system consisting of two points. Dynamics of a system of points. Dynamics of a rigid body. Rotation about a fixed axis. Plane motion. Law of gravitation. Central and dissipative forces. Systems with two degrees of freedom. In his exposition the author follows the method adopted by Maxwell in his book “Matter and Motion,” which represents the best elementary introduction to the “absolute” system of dynamics. At the end of the book a certain tribute is paid to the more abstract and logical approach to considering questions of dynamics. The examples are distinguished by simplicity of calculation. The appendix gives a brief exposition of the “Newtonian” point of view required for the textbook. The present course is intended for students of higher technical educational institutions.

T. LEVI-CIVITA and U. AMALDI, Course of Theoretical Mechanics, vol. I. ONTI, Main Editorial Office of General Technical Literature, M.—L., 1935.

Vol. I, part I. Kinematics. Principles of Mechanics, translated from the 2nd Italian edition by Prof. V. F. Kagan, 383 pp. with drawings, 5,000 copies, 7 rubles 20 kopecks + 1 ruble binding. Parallel title page in Italian.

The best modern large course in mechanics.

* Based on materials of the Review-Bibliographic Department of ONTI.