Bibliography

P. W. Dankwort, Lumineszenzanalyse im filtrierten ultravioletten Licht, fourth enlarged edition, p. 241, Leipzig, 1940.

P. Dankwort, Luminescence Analysis in Filtered Ultraviolet Light, fourth enlarged edition, p. 241, Leipzig, 1940.

The first edition of Dankwort’s book1 undoubtedly played a significant role in the development of luminescence analysis. In that edition, which appeared in 1928, the author did indeed accomplish a major task: he collected together all the literature on luminescence analysis, scattered among journals in a great variety of branches of technology, agriculture, medicine, art, etc., and conscientiously, though uncritically, excerpted it and supplied it with good illustrations. Such a book successfully served the cause of popularizing luminescence analysis and, at the same time, was a good reference work on the luminescence literature and provided the necessary methodological guidance.

However, in the 12 years that elapsed between the first and fourth editions, and even in the 6 years that elapsed between the third and fourth, the reader’s requirements for a book on luminescence analysis have already changed; and although Dankwort’s book has continually been expanded and updated, it is hardly capable, by its very structure, of satisfying the contemporary reader.

Indeed, the period that has passed was one in which luminescence analysis grew rapidly both in breadth and in depth. The number of works that appeared during this time is already measured in the thousands, and the reader now needs not so much a reference book on luminescence analysis—although it must be noted that there is no thorough reference work on the luminescence literature to this day—as a general methodological guide, or a critical survey of the literature on luminescence analysis in one or another field of interest to him.

Each of these tasks is in itself sufficiently large and difficult. Dankwort is trying to solve an obviously impossible task—to provide, in a single monograph, both a methodological guide and a survey of the luminescence literature in all branches of human activity. As a reference work on the literature of luminescence analysis the book may still be useful, although a number of important articles, especially from the years following 1936, are not mentioned in the book.

Dankwort’s book and the analogous book by Radley and Grant (J. A. Radley and J. Grant, Fluorescence Analysis in ultraviolet light, London, 1933) make an especially unfavorable impression in comparison with the recently published monographs by M. Haitinger and Ch. Dhéré (M. Haitinger, Fluoreszenzmikroskopie, 1938; Die Fluoreszenzanalyse in der Mikrochemie, Wien—Leipzig, 1937; Ch. Dhéré, La fluorescence en biochimie, Presses Universitaires,

Paris, 1937). In contrast to Dankwort, these monographs do not claim to encompass the whole of luminescence analysis. The authors limited their task to an exposition of the area in which they possess rich personal experience, and therefore were able to give a number of valuable methodological indications and to approach the literature critically. In accordance with the authors’ special characteristics, Haitinger’s book (Fluoreszenzmikroskopie) gives a more detailed description of instruments and methods, while Dere’s book contains a good critical presentation of experimental facts.

Monographs such as those mentioned will undoubtedly continue to appear. These monographs, written by the relevant specialists, are very necessary, but still more urgently needed is a general methodological guide to luminescence analysis.

One can cite many examples of the crudest errors to which the authors of some articles on luminescence analysis have been led by ignorance of the fundamental principles of luminescence analysis, or even simply by optical illiteracy. We shall confine ourselves to two examples. In luminescence analysis, quenching of luminescence is usually understood as a decrease in the intensity of the glow caused either by physical factors (secondary impact), or by chemical ones (reversible or irreversible reactions). Such a mixing of all quenching factors, although it has no meaning from a scientific point of view, may in practice be justified when the question concerns an indicator for a given fluorescing substance. However, it is utterly meaningless to classify as quenching those cases in which a change in the intensity of the glow of a solution is achieved by introducing into it a substance that absorbs the exciting radiation. Meanwhile, such “quenching” by nitrobenzene of the blue fluorescence of benzine is described in a number of petroleum journals, and Dankwort uncritically reproduces their results.

A second example may be the numerous, poorly substantiated attempts to establish a correlation between fluorescence and a substance by means of the far from typical blue fluorescence. After the work of S. I. Vavilov and L. A. Tummerman, Haitinger, and others, it is known that this fluorescence is universal and is caused by impurities, from which it is comparatively difficult to get rid of. Listing all cases of luminescence described by different authors, without separating out the most characteristic and without distinguishing the best investigations in luminescence analysis (for example, the classical works of Dere, Haitinger, Brugsch, as well as the works of Minnibeck, Kossar, Schlesinger, Brumberg, and others), Dankwort does a disservice to the development of luminescence analysis.

B. Ya. Sveshnikov, Leningrad

1. The second edition is available in Russian translation, Goskhimizdat, 1931. ↩