Physical conditions and the velocity fields in Seyfert 1 galaxies and QSOs

Measurements are presented which give the functional form of the Hβ/Hα and He I lambda5876/Hα ratios with cloud velocity in Seyfert 1 galaxies. Combined with present models of the line-emitting regions, these measurements indicate that the density or ionization parameter increases with increasing velocity. In addition, there is some evidence that the profiles of the Balmer lines become more uniform in the higher luminosity galaxies, which is consistent with the relative profiles of C IV lambda1549 and C III] lambda1909 in QSO's. Finally, arguments are presented which suggest that the line-emitting clouds with the highest velocities are located closest to the central source of ionizing radiation. Subject headings: galaxies: internal motions: galaxies: Seyfert: quasars