Prof. A. K. Timiryazev. The Kinetic Theory of Matter. State Publishing House, M.—P., 1923, p. 319.

Prof. A. K. Timiryazev’s course may be recommended to everyone who wishes to enter into the range of questions of the kinetic theory of matter. Strictly speaking, the content of the book is somewhat broader than its title. The author considers such questions as electron theory and quantum theory, which, of course, already go beyond the limits of the “kinetic theory of gases,” and consequently also beyond the limits of the “kinetic theory of matter.” From our point of view, however, at the present time it is impossible to expound the theory of matter within the framework of the “kinetic theory of gases” alone; such an exposition would be an externally imposed Procrustean bed for the contemporary state of knowledge in this field.

The author sets forth Millikan’s work on determining the charge of the electron, Richardson’s investigations of the Maxwellian distribution in a stream of electrons, Langevin’s theory of magnetism,

the application of quantum theory to the doctrine of heat capacities, the works of Rutherford, Geiger and Marsden, Langmuir, and others. Unfortunately, the author has not touched upon and illuminated all the questions belonging here in accordance with their significance in the modern theory of matter. The question of the nature of molecular forces suffers especially—a question which at the present time occupies a central place in the theory of matter. If one speaks of names, there is lacking, for example, an exposition of Debye’s work on dipoles, and of the works of Eucken, Born, Kossel, Bohr (the theory of valency), and others. The questions expounded are considered with all the mathematical derivations included, which will make the work easier for the reader wishing to understand all the details of the derivation.

In conclusion, one may wish that books like The Kinetic Theory of Matter be published in better external form—on better paper and in a less condensed typeface.

B. Ilyin.