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NEW BOOKS
HALE. New York: Charles Scribner Signals from the Stars. By GEORGEELLERY & Sons. This little book, by Dr. Hale of the Mt. Wilson Observatory, is the fourth in a series of recent aspects and achievements in astronomy. It deals particularly with the possibilities of large telescopes and with the phenomena of the solar atmosphere. Dr. Hale’s own contribution to the science and the large share he has had in the planning and organizing of astronomical research accord him an undisputed authority in these fields; from his previous books the lucidity of his style is too wellknown t o need further comment. An interesting dissertation on lenses precedes the discussion of giant modern telescopes; a chapter follows which deals especially with the observations of the sun’s atmosphere and the correlation between solar and terrestrial magnetic phenomena. The last part of the book is devoted to a description of how the proposed 200-inch telescope might be built, and what it is hoped might be accomplished with it. Not the least attractive part of: the book is formed by the selection of photographs and illustrations. I n particular this reviewer was struck by the remarkable photograph a t the end which so clearly shows the distance effect in the recessional velocities of spiral nebulae. W. J. LUYTEN.
Moderne Physik. Sieben Vortrage iiber Materie und Strahlung. By MAX BORN. 24 x 16 em.; vii 272 pp. Berlin: Julius Springer, 1933. Price: unbound, 18 RM.; bound, 19.50 RM. In 1932 the Technische Hochschule of Berlin and the Elektrotechnische Verein, considering that the remarkable recent developments of physics were of great interest, and might be of great importance, t o electrical engineers, decided t o arrange a series of lectures which should describe these developments in a way generally intelligible to the technical men in question. They were fortunate enough to obtain Professor Born, of Gottingen, who is well-known to all English physicists and physical chemists for his work on the solid state and on the new quantum mechanics, as the expositor, and the book before us is based on the seven lectures which he gave, the matter of those lectures having been worked up and prepared for the press by Dr. Fritz Sauter. Obvious difficulties of the task which Professor Born set himself are the selection of the matter and the rendering of i t in a form understandable without profound mathematics, especially such developments as the principles of wave mechanics and the new types of quantum statistics known by the names of Bose-Einstein and FermiDirac. The selection is very properly dictated by Professor Born’s particular interests, but fortunately they cover the most important aspects of modern quantum theory, and there is a large and fashionable school which will maintain that, as the title of the book implies, this is all that matters in modern physics. The presentation is, considering the nature of the subjects, extremely clear and free fromdifficult mathematics, all detailed calculations being relegated to an appendix, where they are carried through with elegance and with freedom from the more troublesome mathematical technique. It must not be understood that the book is altogether easy reading for a student without previous acquaintance with the subject, but it should present no insuperable difficulties to those, who have a moderate knowledge of the old dynamical theory of gases, and have read some good general account of atomic structure. It is from the kinetic theory of gases that the author, naturally enough, sets out, laying stress on the nature of the assumptions. He then proceeds to deal with the elementary particles, and with the wave-corpuscle dilemma, dichotomy, duality-call it what
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