RYDBERG, J.R. (JOHANNES ROBERT). - REVISION OF THE PERIODIC SYSTEM.

Elektron der erste Grundstoff.

Lund, Håkan Olssons Buckdruckerei, 1906. Lex8vo. Orig. printed wrappers. One of Rydberg's own copies with "Ueberreicht vom Verfasser" printed on frontwrapper. 30 pp., 2 large folded tables (the periodic system).

First edition of important revison of the periodic system in one the author's presentation copies ("Ueberreicht vom verfasser).
"Rydberg’s study of the periodic properties of the elements led him in 1897 to suggest that certain characteristics of the elements could be more simply organized by using an atomic number instead of the atomic weights. This atomic number was to be identified with the ordinal index of the element in the periodic table. In 1906 Rydberg stated for the first time (the paper offered) that 2, 8, and 18 (that is, 2n2, where n= 1,2,3) represented the number of elements in the early periods of the system. In 1913 he went further, correcting an earlier error about the number of rare earths from 36 to 32, thus allowing the n = 4 group to be included in the pattern." (DSB).

Order-nr.: 50386