RYDBERG, JOHANNES ROBERT.

Beiträge zur Kenntniss der Linienspectren I-III + IV (2 papers).

Leipzig, Barth, 1893-94

Both in orig. printed yellow wrappers. 2 Offprints from Annalen der Physik und Chemie, Neue Folge. Band 50. and Band 52. Separat-Abdrucke. Ueberreicht vom Verfasser. pp. (625-)638 + (119-)131. Clean and fine.

First printing of these main papers in spectroscopy of the elements, where Rydberg predicts lines of definite wave-lenghts in the spectrum of one or the other element.

Order-nr.: 59175