In this book Professor Nakaya describes the researches on natural and artificial snow crystals carried out by himself and his colleagues during the last two decades. The material has, for the most part, been taken from papers already published, but the main feature of the book (and presumably the main reason for its publication) is the series of 1550 beautiful photographs of snow crystals. This collection is undoubtedly the finest in existence; the photographs have not been retouched or specially selected for perfect crystal symmetry, so that they are much more representative of natural crystals than, say, the famous collection of Bentley and Humphreys. Moreover, most of the photographs have been taken by oblique illumination allowing both surface and internal structure to be seen.

The first part of the book deals with observations on natural crystals, the physical properties of snow and the classification and frequency of occurrence of the various crystal forms. The second part is largely concerned with the author’s experiments on artificial snow in which crystals have been grown in the laboratory under controlled conditions of temperature and supersaturation.

Most of the material is purely descriptive—there are no mathematics and few numbers. It is not for the crystal physicist seeking information on the structure and growth mechanism of ice crystals; it is a work of art rather than a scientific treatise. For this reason it should have a wide appeal beyond the confines of meteorology and crystal physics.

It is given to few scientists to amass such a beautiful collection of photographs, much less to have them printed on such a lavish scale. This is a handsome publication and a fitting memorial to Professor Nakaya’s lifetime of devoted study in this field. The publishers are to be congratulated on undertaking what must have been a very costly publication, and in keeping the price so reasonable.