kayser heinrich johannes gustav carl (1 résultats)

222 x 154 mm. 8vo. Pages 93-113; (114)-118; (119)-131. [Entire volume: viii, 792, 50 pp.] Tables, 1 fig.; tables; tables. Quarter cloth, marbled boards, gilt spine. Blind stamp of the Carnegie Institution of Washington Solar Observatory. Fine. In 1885, at the Hannover Technical University, Heinrich Kayser, working with Carl Runge, "began his investigations in the field of spectroscopy. In his Handbuch der Spektroskopie (1900) he described the purpose of his investigations: It is certain that the light is produced by the motions of the molecules or of the particles or of their electrical charges. It was expected that chemical elements would be similar to a certain extent in the structure of their spectra according to their periodic classification. Balmer was the first who derived a real result of regularity in the distribution of the wave numbers of the spectral lines of hydrogen. It was hoped that similar laws would be detected for other elements. "Kayser and Runge began these investigations at about the same time that Rydberg began working along the same lines. Kayser and Runge determined the spectra anew, using a Rowland concave grating, and found the results to be much more reliable from this method; Rydberg evaluated the existing older measurements anew. The investigations showed that for many elements a regular structure could indeed be demonstrated. For the alkali metals (lithium, sodium, potassium, rubidium, cesium), all known spectra lines could be settled at three series described very accurately by equations of the same structure; these formulas were also interrelated. Furthermore, an important relation between the atomic weight and the structure of the spectra was discovered. Kayser and his co-worker learned not only that the spectra of these five related elements were ordered by the same plan, according to the increasing atomic weight. "Kayser and Runge next investigated, with similar results, the alkali earths and also some metals of the groups IB and IIB of the periodic table of elements. The regularity was not so perfect in this case, however. Kayser said that the number of irregular lines grows as one proceeds in the natural system of elements. He emphasized that the formulas he and his associate had found in Hannover, as well as those of Rydberg, were only empirical and far from the discovery, through the structure of the spectra, of the behavior of the atoms. In his criticism of Rydberg, Kayser was always willing to acknowledge the merits of Rydberg's work. From the vantage of today, the work of Rydberg and of Kayser and Runge was indispensable to the atomic theory brought forth twenty-five years later by Rutherford and Bohr. [Emphasis added.] Although Kayser provided the solid experimental foundation for this theory with his experiments - he was the experimenter, Runge the theorist - Rydberg, full of ideas and speculations, was more successful in formulating the spectra equations; hence the name Rydberg constant. Nevertheless, Kayser and Runge's lists of the exact frequencies of many spectral lines guarantee their place in the history of science." [Emphasis added.] DSB, VII, pp. 267-268.