‎"RYDBERG, J.R. (JOHANNES ROBERT).‎
‎Om de kemiska grundämnenas periodiska system.‎

‎Stockholm, P. A. Norstedt & Söner, 1885. 8vo. Uncut, unopened in the original printed wrappers. In ""K. Scenska Vet.-Akad. Handlingar. Band 10. No. 2"". Fine and clean. 31 pp, + 2 plates.‎

Reference : 52994

‎First appearance of Rydberg's important paper on the periodic table in which he intruduced atomic numbers and made his famous conclusion: ""The discovery of the periodic system have made it impossible to consider the chemical elements as simple and independent, and it has thus become a matter of great interest to searching explain the context between them. [...] And it would certainly confirm that the differences [between the atomic weights] periodically change, one must assume that the atomic weights themselves grow after a periodic law when it progresses in the system, and thus are to be regarded as periodic functions of their number. ""Rydberg’s most significant scientific contributions were to spectroscopy: but his involvement with spectra had its origin in his interest in the periodic system of the elements, an interest that endured throughout his professional life. His earliest published papers in physics dealt with the periodic table. In the introduction to his major work on spectra (1890), he stated that he considered it only a part of a broader investigation, the goal of which was to achieve amore exact knowledge of the nature and constitution of the chemical and physical properties of the elements. He held that the effective force between atoms must be a periodic function of their atomic weights and that the periodic motions of the atoms, which presumably gave rise to the spectral lines and were dependment on the effective force, thus might be a fruitful study leading to a better knowledge of the mechanics, nature, and structure of atoms and molecules and to a deeper understanding of the periodic system of the other physical and chemical properties of the elements. In line with contemporary conceptions, Rydberg’s view was that each individual line spectrum was the product of a single fundamental system of vibrations."" (DSB)‎