V. SHULEIKIN. Physics of the Sea, vol. I. Dynamics of the Sea, Thermics of the Sea, Optics of the Sea. GTTI, Moscow—Leningrad, 1933.

Until comparatively recently, the study of the processes occurring in the liquid and gaseous envelopes of the terrestrial globe was descriptive in character. Although attempts had been made many times, in one form or another, to apply mathematical analysis and the techniques of mathematical physics to the investigation of physical phenomena occurring in the liquid and gaseous envelope of the terrestrial globe, nevertheless we can count only a relatively small number of works in which the problems of the physics of the sea and of the atmosphere were posed and solved with that degree of precision which is proper to any physical science. Here one must point first of all to the remarkable works of Helmholtz, which dealt with the circulation of the atmosphere caused by the rotation of the earth and examined from a hydrodynamical point of view, and to the theory of waves on the surface of large bodies of water, likewise developed by Helmholtz. As a large body of knowledge accumulated in the field of the study of physical phenomena in the liquid envelope of the earth, and as more precise numerical material was accumulated in this branch of science, more and more attempts were made to approach, by purely physical means, the question of the processes taking place in the sea.

Shuleikin’s book belongs precisely to those trends in the study of the sea in which physics is placed in the foreground, and in which the processes occurring in the liquid envelope of the terrestrial globe are treated from the standpoint of modern experimental and theoretical physics. This book is of all the greater interest because the author himself for many years worked on problems of the physics of the sea and obtained results in this field that are outstanding in interest. These results were obtained chiefly at the Black Sea Hydrophysical Station, founded by him in 1929 at Katsiveli (Crimea), and find their place in an interesting and extensive course, the first volume of which appeared in 1933.

Shuleikin begins his exposition with the dynamics of sea currents; along with data of an experimental character he gives the hydrodynamical equations of these currents and sets forth the modern conception of them. To facilitate understanding of this chapter, where knowledge of hydrodynamics is required, Shuleikin gives a derivation of the fundamental equations of hydrodynamics in Eulerian form and in Lagrangian form. Making use of hydrodynamics, he sets forth Bjerknes’s theory and gives an application of this theory to the study of established sea currents. In this chapter Shuleikin does not confine himself only to the general conditions of flow of an ideal fluid, one that gives no representation of friction, but shows how the effects of friction in water can be taken into account; moreover, he sets forth a convenient method for studying currents, due to Ekman. This first part ends with a study of set-downs and surges.

water, first posed by Shuleikin, and to the study of the influence of bottom relief and the investigation of elements of currents in certain concrete cases.

The second part is devoted to the dynamics of the tidal wave. In accordance with the theory of tides, Eri determines the length of the tidal wave and its energy. He considers the motion of this wave in a channel of variable cross section and gives an application of this theory to concrete cases of tides in the White Sea. This case, first studied by the author of the present work, is of interest because the tidal phenomena that produce periodic oscillations of the water level are connected with resonance in a closed sea, which constitutes a Helmholtz resonator in which the eigenperiod is adjusted to the period of those oscillations that are produced in the open sea. Further on, the interesting and important question of seiches is considered, and seiches under a complex bottom relief are described. The chapter ends with an indication of the influence of the earth’s rotation on tides and with a study of tidal friction; moreover, the method for determining the elements of a tidal wave in the open sea is set forth. In this field Shuleikin also carried out interesting investigations and constructed instruments that make it possible to determine the heights of tides and ebbs in the open sea or ocean.

In the third part, the question of the dynamics of surface and internal waves is treated. In this part Shuleikin gives a general picture of the motion of water in the open sea and then indicates the impact of waves on obstacles, vividly showing the enormous destruction caused by waves (using as an example the fall of the “Monk” rock in Crimea, Simeiz). The author then describes a method for studying the form of waves by means of special instruments, constructed by him, either from the shore or while on a ship. This chapter ends with the study of internal waves.

In the fourth part, the heat balance in the sea is studied. Of extraordinary interest in this chapter are investigations of direct solar radiation and diffuse radiation from the celestial vault by means of instruments used at the Black Sea Hydrophysical Station, and the design of these instruments belongs to Shuleikin. There, too, are studied the ray-emission processes of temperature equalization in the sea as a result of the mixing of water masses.

Next are set forth the thermics of the ice cover and certain elements of the normal and anomalous thermal regime of the earth.

Investigations of the evaporation of water, which plays an enormous role in the thermics of the sea, occupy a considerable part of this chapter; moreover, all the instruments used for this purpose were constructed and studied by Shuleikin, so that this chapter also has an original character.

In the last, concluding part, in the optics of the sea—which in its contemporary form was created chiefly by Shuleikin’s works—the author gives a picture of the optical processes in seawater, shows what role is played by the absorption of light by water and by the molecular scattering of light by large and small inclusions, and investigates how the color of the sea depends on the conditions of absorption and molecular scattering of light. Further on, Shuleikin considers the light processes occurring at great depths, and ends this chapter with the origin of sea color and an exposition of the methods of hydro-optical determinations used by him in the hydro-optical laboratory he created at Katsiveli.

The whole book is, not only in form but also in its very essence, an extremely original and interesting work. It is a genuine physics of the sea, written by a person well acquainted both with physical-experimental processes and with the processes occurring in the sea. The book deserves the widest attention not only from geophysicists and physicists, but also from all persons whose activity is in one way or another connected with the processes occurring in the sea; and we may wish that this excellent book find the broadest possible distribution among all interested persons.

P. Lazarev