  We present high-quality aperture synthesis observations of the neutral
hydrogen distribution in a sample of five galactic systems believed to be
involved in progressive stages of merging: Arp295, NGC4676, NGC520, NGC3921,
and NGC7252. These data are supplemented by wide-field images taken through a
narrow band Halpha filter, and by deep R-band surface photometry. In the early
stages, large amounts of HI exist within the galactic disks and star formation
is widespread. The ionized gas emission often takes on the appearance of plumes
and arcs emanating from the nuclear regions, which are presumably the sites of
interaction induced starbursts. In the final stages there is little if any HI
within the remnant bodies, and tidal material is seen moving inward. This
suggests that these remnants will evolve into elliptical galaxies in their
atomic gas contents as well as their photometric properties. However the
observations of NGC520 reveal an extensive rotating gaseous disk, suggesting
that perhaps some mergers will not destroy the atomic gas disks of the
progenitors. Overall, large quantities of both gas and starlight are seen at
large radii. Since this material evolves on very long time scales, it may leave
observable signatures for many Gyr.
