Bibliography

today, when studying wave optics, students often make use of the results of wave mechanics, and not the other way around; and the textbook under review fully corresponds to this situation. It is strongly felt in it that the authors give themselves a clear account of the readership for which the textbook is intended. For it often happens that an author, striving to satisfy the needs of all readers, piles up in a single book both elementary relations (the formula de Broglie) and an exposition of new works, the understanding of which is difficult even for a specialist.

The reader for whom the authors of this book have planned it is an ordinary student studying physics or physical chemistry and approaching the study of wave mechanics for the first time. The chemical bias of the book is determined by the selection of material. In the form of applications of new ideas, mainly the problems of molecular structure and the nature of the forces of chemical bonding are taken. But precisely in this lies the value of the book. The authors not only present the methods, but also make it possible to become acquainted with applications of these methods in concrete examples.

Having worked through this book, everyone will feel that he has mastered wave mechanics, albeit in a somewhat narrow range, but fully and thoroughly.

The book contains the following chapters:

I. An introductory chapter on classical mechanics, containing the necessary information and preparing for the transition to the new mechanics.

II. The old quantum theory of Bohr. This chapter is useful because the terminology and visual representations of the old theory still find broad application even now.

III and IV. Schrödinger equation for one and many particles.

V. The hydrogen atom. This chapter is distinguished by particular clarity of exposition and contains a large number of diagrams facilitating assimilation of the subject.

VI and VII. Approximate methods. In these chapters, besides the usual theory of perturbations, variational and other approximate methods for solving problems of quantum mechanics are presented.

VIII. The theory of molecular structure and the nature of the chemical bond.

The last two chapters contain a very brief, but sufficiently comprehensible, exposition of quantum statistics and of the doctrine of the symmetry of the elements of matrix mechanics.

Yu. Rumer

Eisen, Magnetische und elektrische Eigenschaften des reinen und kohlenstoffhaltigen Eisens. bearb. v. Auwers. B., Verl. Chemie, 1934, XXVI, S 1421—1634, Fig. (Gmelins Handbuch der anorganischen Chemie, Tl. A, Lfg 7), Mk 36.

Iron, magnetic and electrical properties of pure and carbon-containing iron.

The book is the 7th fascicle of part A of the 59th volume of the Gmelin handbook (Gmelin’s Handb. der Anorg. Chemie), published by the German Chemical Society under the editorship of Meyer and Pietsch. The 59th volume is devoted to iron. Its part B, consisting of 5 fascicles, contains a description of iron compounds.

As can be seen from the prospectus, the editors sought to take into account in the volume devoted to iron the exceptional significance that this metal has in the economic and cultural life of all peoples. In chapters devoted to the chemical technology of metals, it was impossible to consider questions of metallurgy, mechanical processing, and the application of metals without illuminating, to a certain extent, their physical properties.

In the present fascicle the author has given a very complete monograph on the magnetic and electrical properties of iron and its carbon compounds, going beyond the bounds of a chemical handbook; and it has acquired the character of a reference book more interesting for physicists and electrical engineers than for chemists. The editors justify this by saying that in handbooks on pure

in physics or electrical engineering the exposition is usually limited to a consideration of physical phenomena alone, without due account of the properties of the substance and materials in which the process takes place. This is to a certain extent true, and therefore textbooks have already begun to appear in the Soviet Union that take into account the real conditions under which electromagnetic processes occur in metals. If this aim is pursued in a chemistry handbook, then, since a chemist-reader cannot be assumed to have detailed knowledge of magnetism, it is necessary to present the laws of magnetization in such an expanded form that even complex physical conditions of these phenomena are completely clear to a non-physicist. Auwer’s handbook, of course, does not achieve this aim.

Let us briefly give the contents of the volume.

A. Magnetic properties of iron and carbon steels. Definition. Dimensionality of characteristics. Units. Theory of ferromagnetism (old and thermodynamic theories, theories based on taking into account the properties of the atom and of the crystal lattice, the relation between ferromagnetism and other physical properties). Magnetic properties of the atom. Magnetic properties of the material. Magnetization. Induction. Pure iron. Carbon steel. Susceptibility. Permeability. Iron. Steel. Hysteresis. Iron. Steel. Permanent magnets. Barkhausen effect. Iron. Steel. Wiedemann effect. Iron. Steel. Einstein–de Haas effect. Barnett effect. Galvanomagnetic and thermomagnetic effects (9 different effects are considered). Magnetophoresis.

B. Electrical properties of iron–carbon steels. Electrical properties of the atom. Electric moment. Excitation, resonance, and ionization potentials. Electrical properties of the material. Electrical resistance. Iron. Steel. Thermoelectric properties of a homogeneous material. Benedicks effect and Thomson effect. Iron. Steel. Dielectric coefficient. Iron in contact with solid and liquid substances. Electrization by friction. Electrostriction. Contact potential difference. Rectifying action of the contact of iron and steel with other substances. Thermoelectric properties (about 60 pairs of iron and steel with various metals). Peltier effect for iron and steel (15 different pairs). Iron in contact with gases and vacuum. Electrization by friction. Contact potential difference. Cathode and anode potential drop. Cathodic sputtering. Discharge between iron electrodes. Electron emission. Emission of positive ions. Absorption, reflection, and diffraction of α, β, γ and cosmic rays. Electrophotophoresis.

The list of chapters given indicates the very varied content of the book and confirms that the material selected by Auwer by its content could also have found a place in a physics handbook. In the subtitle of the note (p. 1421) it is indicated that, in presenting the physical properties of iron and steel, magnetic and electrical properties, for external reasons, came first. They are followed by a description of mechanical and thermal properties (issue 8 of part A) and then an exposition of optical properties.

In the introduction it is explained that throughout the entire volume the magnetic and electrical properties of pure iron are considered separately from the properties of materials containing carbon. Individual studies are cited in one chapter or another depending on the formulation of the question in the given investigation; thus iron containing only 0.004% C sometimes falls into the group of carbon steels if in the corresponding investigation the subject of study was the influence of carbon content on magnetic properties. In another case the influence of treatment on the properties of iron may be described in the section on pure iron, despite the fact that the material in question contains tenths of a percent C. Thus the concept of pure iron, for reasons of expediency, turns out to be broader than usual.

The booklet is chiefly in the nature of a detailed index of the literature: on almost every page up to half the text is occupied by the titles

cited works. The material presented by Auvers is usually given without any criticism, and the author often treats the presentation of one or another researcher with excessive trust. If the cited material is accompanied by critical remarks, the latter are not always apt. There are inaccuracies caused by insufficient familiarity with the cited literature, as a result of which the distribution of articles by sections sometimes does not correspond to their content. Cases of careless exposition are frequent. Many important works are only cited.

On p. 1441 the author sets forth the important relation between the external field \(H_e\), which magnetizes the body, and the internal field \(H_i\), which magnetizes the substance of the body,

\[ H_i = H_e - NI. \]

This cardinal law of the influence of the shape of a body on magnetization, usually difficult to grasp when studied, is explained here in passing, with a laconic reference to the drawings placed nearby, which correspond little to the case. In Fig. 575 the superposition of the external field of the body on the field \(H_e\) is shown, while in Fig. 576 the thickening of the field inside the body is shown for the induction lines; the weakening of the field inside the body is not visible from the drawings. Moreover, the drawing itself (Fig. 576) is inaccurate: in it the induction lines enter the ferromagnet without refraction.

Next a formula is given for calculating the demagnetizing factor of an ellipsoid \(N\), and it is not stated that it is suitable only for an elongated ellipsoid; the statement is erroneous that the parameter \(p = \frac{d}{e}\) instead of \(\frac{e}{d}\). With the degree of detail with which information is given in this section, it would have been necessary to indicate the distinction between the so-called ballistic and magnetometric demagnetizing factors. On p. 1442 it is stated in general form that the law \(H_i = H_e - NI\) is valid only for \(I < 1000\): this is true for certain bodies with inhomogeneous magnetization, in particular for cylinders, but with respect to the important case in measurement practice of an ellipsoid, no such limitation exists; in this, in particular, lies the value of the ellipsoidal form of specimens.

Most inaccuracies occur in the parts of the handbook dealing with magnetization in variable fields. It must be noted that the theoretical side of this question is little known to foreign authors, since the most fundamental works on magnetodynamics have been carried out in the USSR, while abroad people usually deal only with the empirical side of the matter.

Auvers incorrectly understands the magnetic conductivity introduced by Soviet authors, which is nothing other than taking account of the lag of induction behind the field in periodic processes. The existence of magnetic conductivity in no way depends on the resonance or natural oscillations of elementary magnets, as the author thinks; it owes its existence only to hysteresis, whether quasistatic or dynamic. Since the latter is manifested also in the theoretically conceivable resonance of elementary magnets, magnetic conductivity can, as a particular case, figure here as well. The author mistakenly thinks that it appears only in the latter case. Therefore the passages on pp. 1445 and 1486 are the fruit of a misunderstanding. In the last paragraph the internal friction, determined from the rotation of the atom, is transformed into internal friction referred to the gram-atom. Here, too, the reference to Essen’s paper, which supposedly writes about magnetic conductivity, is erroneous. The author quite often refers articles devoted to Foucault currents and the skin effect to articles on magnetic conductivity and on the specific lag of magnetization caused by magnetic viscosity. This explains the inappropriate citation here of V. K. Arkad’ev’s work from Elektr. Nachricht. Technik, 1933, on p. 1445, and of A. A. Ermolaev’s work on p. 1415.

On pp. 1483—1485 there is a very detailed numerical summary of the values of the permeability of iron and steel for 77 different frequency intervals. These data, obtained by various authors by means of the most diverse methods in fields of different and rarely known exactly intensity,

relate to materials of poorly determined composition. Many of the cited data are obsolete. Therefore this extensive table, occupying 3 pages, does not have the value that would justify its occupying so much space in the book. It would have been more expedient to take data on the course of permeability with a larger selection and to present it graphically as a function of frequency, in the form of curves (magnetic spectra). On p. 1486 the formula for calculating \(\mu\) from observations in wires of finite length is carried over from the original incorrectly; the denominator should contain \(\lambda\), not \(\lambda_\circ\). The note on p. 1502 is inaccurate, stating that, according to Gerlach, the magnetic viscosity of iron is already very large at frequencies from 0.12 to 2 Hz. Gerlach in fact speaks of a single kind of iron, discovered by him accidentally, for which the viscosity was exceptionally large, which this iron owes to impurities. On p. 1500 the author confuses the noise during magnetization of iron, caused by stepwise magnetization, with the sound caused by an audio-frequency current passing through an iron rod. Both phenomena may be due to magnetostriction, but in the second phenomenon, on which Reis’s telephone of 1861 is based, the sound belongs to the external source, and not to the iron itself. In the part dealing with the conductivity of iron, there is no information on the resistance of iron wires to alternating current, whereas this question, connected with the replacement of copper by iron in the electrical industry, is of great economic interest, and it would fully correspond to the technological orientation of this part of the monograph.

We shall not go more deeply into further analysis of the book. What has been said is sufficient to confirm the opinion expressed at the beginning concerning its shortcomings.

Despite the latter, with careful use it may more than once be of service in reference work and in becoming acquainted with the extensive literature on the magnetic and electrical properties of iron and carbon steel.

It would be very desirable to have a similar reference book in Russian, but only on condition that its extreme brevity be eliminated, that all incorrect and erroneous statements be corrected, and that it be supplemented with quotations from the Soviet technical press. At the present time we already possess a vast literature on these questions, as is evident from the Messkin—Kussman handbook, Ferromagnetische Legierungen, where articles from Soviet journals occupy a very prominent place. They often attract the attention of foreign specialists, as is evident from requests received from abroad to send one or another book or journal.

V. Arkad’ev.

FOREIGN BOOKS ON PHYSICS FOR 1934 AND 1935, INDICATED IN THE PRESS FOR JANUARY—AUGUST 1935

ABBAGNANO NICOLA. La Fisica nuova. Fondamenti di una teoria della scienza. Napoli, Guida, 1934. X, 120 p. L. 7.

Annales de la Faculté des sciences de l’Université de Toulouse, pour les sciences mathématiques et les sciences physiques, publ. sous les auspices du Ministère de l’Instruction publ. par un comité de rédaction composé des prof. de mathématiques, de physique et de chimie de la Faculté P., Gauthier Villars, 1934, 267 p.

ARNULF A., IVON G. et GRAMONT A. de. La Mesure des formes locales et des petites épaisseurs. P., Revue d’optique théorique et instrumentale, 1935. Fr. 7.

AUDUBERT N. et QUINTIN N. Travaux pratiques de physique et de chimie physique, P., Vigot, 1934, 151 p., fig., Fr. 25.

BLACKETT P. M. S. La Radiation cosmique. Aperçu général. La Méthode de la chambre Wilson command. par compteurs de Geiger-Müller. L’Action du champ magnétique terrestre. La Perte d’énergie par ionisation. P., Hermann, 1935, 4 Vol. (Actual, scient. et industr. N 230—233, Confe-