Investigations of Atomic and Molecular Absorption Spectra III: Ultra-Violet Absorption Spectra of Indium Vapour

By use of a King furnace the absorption spectra of In vapour in the near and vacuum ultra-violet have been observed. Fourteen new absorption lines of the In I b spectrum have been found in the Schumann region, and the normal sharp and diffuse series extended. Classification of the strongest of the vacuum ultra-violet lines leads to an amendment of the sp 2 term assignments of McCormick and Sawyer in the isoelectronic spectrum of Sn II.