Splitting of absorption lines in 3C 191

Spectroscopic observations of the quasar 3C 191 have been made at a higher dispersion than previous studies in an attempt to detect absorption from the excited fine-structure level of the ground state of C ii. It was found that the previously studied absorption system is split into two systems (z/sub A/ =1.945, z/sub B/=1.949), which show apparent line-locking on the C iv lambda1550 doublet. Both systems show a similar and wide range of ionization. The results are interpreted in terms of a multiple cloud model which is photoionized by a central source, and the possible implications for the ionization structure in QSOs generally are discussed. (AIP)