Modern Problems of Natural Science. Physics, under the general editorship of Acad. P. P. Lazarev, No. 1: K. Fajans. Radioactivity and the Modern Theory of Chemical Elements. Translation and additions by E. V. Shpolsky. State Publishing House, Moscow, 1922. Pp. 127.

The richness of the content of Fajans’s small book can best be conveyed by listing the titles of some of its chapters:

“II. Radioactive transformations of elements.
III. The chemistry of radioelements.
IV. The displacement rules and their applications.
V. Atomic weight and the lifetime of isotopes.
VI. The final products of radioactive series.
VII. Properties of isotopic elements.
VIII. Isotopy among ordinary elements.
IX. Ordinal numbers of the elements.
X. The structure of the atom.
XI. The artificial decomposition of the nitrogen atom.
XII. Revision of the concept of the chemical element.”

The exposition, despite all its brevity, is very clear. There is no doubt that anyone seriously interested in physics and chemistry will be warmly grateful to the editors of Modern Problems of Natural Science for the fact that,

that, through the translation of Fajans’s little book, she has enabled the Russian public to become acquainted, in summary form, with one of the most important scientific achievements of the twentieth century.

The outward appearance of the edition is satisfactory, with the exception of Figures 2 and 8. It has such features, necessary in any serious book, as a table of contents and indexes of names and subjects. There is even—something to which we are not accustomed—a list of misprints, unfortunately a very incomplete one.

The additions made by the translator are very valuable.

One further comment.

There are two ways of rendering foreign names in Russian books. One—not without certain objective merits and very convenient for Russian authors or translators—consists in preserving the original spelling by means of Latin type. The other, far more troublesome for the Russian author (or translator), but far more desirable from the reader’s point of view, is the transcription of the foreign name in Russian type. One may prefer either method; but, having chosen one, one should adhere to it. In the present book we find a strange mixture of both methods: thus, on p. 16 we read: “Curie and Debierne succeeded in obtaining...”; on p. 17: “W. Gray and Sir William Ramsay even succeeded in finding the weight of a definite volume of emanation...” and so on.

A. Bachinsky.