P. P. Lazarev, Energy, Its Sources on Earth and Its Origin. Gosenergoizdat, Moscow, 1947, 230 pp., 63 figs., with index.

The book under review is evidently the last work of the late Academician Petr Petrovich Lazarev. The main interest of this work, as it appears to us, lies in the fact that, under a single cover, the most diverse fields of physics, physical chemistry, and biological chemistry are brought together, their exposition being conducted from a single point of view—the energetic one. The aim of the book is to examine consistently all the energy resources with which man comes into contact in his technical activity and life. At the same time, the question of the use of energy of one type or another is considered by the author from several sides. The history of the question is briefly set forth, the physical essence of the phenomenon is discussed, its industrial significance is clarified and illustrated with figures. The prospects for using energy of the given form are also outlined, and almost always interesting technical comparisons of the practical significance of energy resources of different types are made.

It is therefore even somewhat difficult to determine for whom this book is intended. It can undoubtedly be recommended to the physicist, the chemist, the biologist, and the engineer. Each of them will find here, alongside things well known to him, an exposition of questions new to him. And since the exposition is conducted from a single point of view that is interesting to each of these specialists, each of them will read this book with great interest. The degree of qualification of the reader may also be very varied. Parts of the exposition, written by Petrov, require a knowledge of mathematical analysis, though, to be sure, in a very modest volume, corresponding to the first courses of technical higher educational institutions. The main text is intended for knowledge provided by secondary school. Yet there is no doubt that the reader must possess general culture and the habit of reading scientific literature. In short, the book cannot be called popular, nor does it lay claim to being so. In any case, the author set himself the aim of explaining everything “from the very beginning.” Thus, in the exposition of the fundamental laws of thermodynamics, the essence of the graphical representation of ther—

... thermodynamic processes. The exposition of the foundations of organic chemistry is conducted as though the reader were encountering the concept of valence for the first time. It is also assumed that the reader is unaware of the equality of energy quanta to Planck’s constant multiplied by frequency, and so on. At first glance one is surprised by such a dissonance between the generally high level at which the exposition is conducted and the presence in the book of such elementary matters. On more attentive reading, however, it becomes clear that this is no accident. The author undoubtedly counted on the fact that his book would be read by people of the most diverse specialties; they would skip the chapter dealing with questions close to their own, while the remaining parts of the book they would be able to assimilate easily only with such an exposition “from the very beginning.”

The book is divided into two parts. In the first are set forth the foundations of thermodynamics and of the law of conservation of energy and matter. In the second, special part, various energy resources are considered in succession.

The first chapter sets forth the history of the discovery and the experimental proofs of the law of conservation of mass. The second considers the history of the discovery and gives the modern formulation of the law of conservation of energy. The third chapter examines Einstein’s relation between mass and energy. In order to show how this relation is confirmed by experiment, the structure of the atom and of the atomic nucleus and the mass defect are briefly considered. In the concluding paragraph of this chapter the final formulation of the law of conservation of matter is given as a single law synthesizing the laws of conservation of mass and energy. In the last chapter of the general part the second law of thermodynamics and Nernst’s theorem are considered. Petit gives here, in a very compressed form, all the calculations concerning the equation of state and the formula for the work of all thermodynamic processes. The purpose of these calculations is, as usual, to show the reader that the efficiency of the Carnot cycle will have the maximum possible value. Perhaps for readers who are not able to read Petit’s text (which requires knowledge of differential and integral calculus), this part of the chapter devoted to the second law of thermodynamics will remain poorly understood. Much more successful are the paragraphs of the main text in which the concept of probability and the application of this concept to the interpretation of the second law are briefly expounded. Petit gives the derivation of Planck’s relation connecting entropy with the probability of a state, and Nernst’s theorem.

The first section of the special part is devoted to chemical sources of energy. This section is the main core of the book. In a separate chapter the question of the energy of organic compounds is considered, and the heats of combustion of a whole series of organic molecules are presented. The remaining part of the chapter is an elementary exposition of the foundations of organic chemistry. The question of valence is set forth, as mentioned above, “from the very beginning,” and moreover in an excessively simplified way (atoms with hooks).

The next chapter is devoted to explosive substances. After presenting the history of the question, the author examines in considerable detail the chemistry of some of the most important explosive reactions and the physical processes occurring in an explosion. The chapter ends with a brief economic survey of the practical application of explosive mixtures.

In the following chapter, entitled “Foundations of the Theory of Photochemical Reactions,” the author considers the entire process of the evolution of energy in a green plant, beginning with the formation of the simplest carbohydrates and ending with the formation of starch and cellulose in the trunks of trees. This chapter gives many interesting experimental data on the influence of light on plant growth. Partly in this chapter and partly in the following one, the problem of carbon assimilation is examined in detail. Having shown in these two chapters that the energy of solar radiation accumulates in tree species in the form of chemical energy, in the following chapter the author shows the further conversion of this energy into the heat-producing capacity of tree species. Here are considered

origin and composition of coal and peat. Several pages are devoted to an analysis of the world reserves of coal. The next chapter is devoted to oil. The biological-geological and physicochemical theories of the formation of oil are treated in detail. In setting forth the latter, the author follows Mendeleev. The section entitled “Chemical Sources of Energy” also includes a chapter on the origin of muscular force. Here the author discusses the transformations of food introduced into the organism of an animal, and briefly dwells on the mechanism of the conversion of the chemical energy of food substances into the mechanical energy of muscular tissue.

The second section of the special part of the book deals with the energy of the wind and the energy of moving water. The formation of air currents is considered descriptively. The concepts of the constant circulation of the atmosphere and of local air currents are explained. The reader also receives an idea of seasonal winds. The book says plainly not enough about possible ways of using blue coal—there is not even a diagram of the operation of the simplest wind engine.

In the chapter on white coal the author examines in detail the nature of the occurrence of snow and ice in mountains. The description of the properties of glaciers is accompanied by a description of the plastic properties of ice. These properties of ice are connected with the motion of glaciers. It is shown that the basis for understanding all glacial phenomena is the law of the change in the melting point of ice with pressure. The remaining—disproportionately small—part of the chapter deals with the origin of mountain rivers and with the utilization of the energy of their flow. The last pages are devoted to the economic importance of white coal.

Of interest is the small chapter on the utilization of the energy of tides. Here the cause of these phenomena is described, Shuleikin’s instrument, which makes it possible to study tidal waves, is described, and, finally, an economic survey of the problem is given.

In the last chapters, which constitute the third section, several pages are devoted to the direct use of solar rays, and also to methods of using small temperature differences for the construction of engines.

The main part of the last small section—“Atomic Energy”—was written by E. V. Shpolsky. Here the construction of the Van de Graaff machine and the cyclotron is briefly set forth, and the possibilities of using nuclear reactions are described.

As regards completeness of exposition, the book is written very unevenly. The general part probably occupies a disproportionately large space. And in the special part, too, a number of questions are treated extremely cursorily.

It is quite understandable that the author’s interests have left their mark on the content of the book, and that questions close to him occupy somewhat more space in the book than they deserve in comparison with other problems. In spite of this, the book leaves a sufficiently unified impression, and one can only repeat once more the conviction expressed by us at the beginning of the review: that the book will be read with interest and profit by persons of the most varied specialties.

A. I. Kitaygorodsky