| Abstract | Neutral hydrogen spectra at 21 cm wavelength of the early spiral galaxies NGC 984, NGC 5318, NGC 2911, and Mrk 331 are reported. Absorption features were detected in these four galaxies. The velocity gradients and total column densities of the absorptions suggest that they arise in clouds that are located in the central parts or in the warped disks of the galaxies. For the sample of 10 galaxies with known emission-absorption profiles, there is a weak statistical preponderance of infall over outflow of H I toward galactic nuclei. |
