774
S E W BOOKS
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Vakuumspektroskopie. By H. BOMKE. 22 x 14 cm.; x 248 pp. Leipzig: J. A. Barth, 1937. Price: 17.70 RM.; bound, 19 RRI. Although the vacuum spectrograph has played a very important part in problems of analysis of both atomic and molecular spectra, Lyman’s Spectroscopy ofthe Estreme Ultra-violet is the only book that has hitherto dealt exclusively with this subject. When the second edition of that well-known monograph appeared in 1928, the region first penetrated t o 1250 A.U. by Schumann with a fluorite spectrograph had been extended t o about 500 A.U. by Lyman and to 136 A.U. by blillikan and Bowen with concave gratings a t normal incidence.. At that time, too, Thibaud and Hoag had used gratings (plane and concave, respectively) a t grazing incidence, an arrangement which had previously been used by A. H. Compton for x-rays only, and which has advantages over the normal-incidence mounting in regard t o compactness, intensity, and dispersion; they did not succeed, however, in reaching Millikan’s 136 A.U. limit. Working from the soft x-ray side and using glass gratings (plane and concave, respectively) a t grazing incidence, Thibaud and Osgood had extended the upper limit of wave-length measurements, and Osgood’s observations had closed the gap between x-ray and optical wave lengths. It is since the appearance of Lyman’s second edition, however, that the most rapid progress has been made. In 1929 Ericson and E d l h , working in Siegbahn’s laboratory a t Uppsala, announced their first results on the measurement and interpretation of very short wave lengths emitted by highly ionized light atoms. Since then grazing-incidence grating technique has been further improved, and the apparent optical limit is now about 30 A.U. (EdlBn, 1936). Bomke’s connected account of all this work is ITelcome; no u orker in the extreme ultra-violet can afford t o be without i t . About one half of the book describes the instruments and methods employed, and most of the other half deals with the results obtained. The treatment of atomic spectra is fuller and much better than that of molecular spectra. The tables include EdlBn’s standard wave lengths between 1371 and 160 A.U., and the ground states and ionization potentials of all the atomic emitters; the latter table will be found particularly useful, but could be set out in a rather more compact and instructive form involving less printing of spectroscopic notation. S o t the least valuable feature of the book is a list of 626 references. W. JEVOXS.
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Anschauliche Quanientheorie. By P. JORDAN. 24 x 17 cm.; xii 320 pp. Berlin: J . Springer, 1936. Price: 12 RLI. This book is an important contribution t o the literature, coming as it does from such a well-known worker on various aspects of the quantum theory. It may perhaps be doubted, in spite of its fundamental importance, if i t is the kind of book which is likely t o attract the attention of the average physical chemist. It is a very different type of work from that of Pauling and Kilson, for example, where a successful effort vias recently made to transmit t o the experimental chemist and physicist the technique involved in the working out of applications of the theory. Dr. Jordan’s book is concerned much more with the skeleton, the bones, and sinews of the quantum theory itself than x i t h its applications. His book is divided into five chapters, the first of which contains a very clear account of the fundamental experiments of quantum physics. This is followed by an equally clear theoretical analysis of these experiments; Schrodinger’s equation is not in fact dealt with until page 110. The third chapter is rather hard going and deals with quantum and wave mechanics in some detail; this part of the book involves discussion of matrices and statistical transformation theory. The fourth chapter is concerned with many-body problems and elementary particles. Finally there is a somen h a t philosophical chapter on the relation between atoms and organisms.
