  We present a small data base of homogeneously derived photospheric element
abundances of DZ white dwarfs and related objects. Our previous investigations
are supplemented with the analysis of ultraviolet spectra for nine white
dwarfs. Of particular interest is the detection of Lalpha absorption in van
Maanen 2 and a determination of the effective temperature of this star. The new
value is about 1000K lower than previous results due to the strong ultraviolet
absorption by metals which has to be considered consistently. The metal
abundances of our sample stars are compatible with the predictions from the
two-phase accretion model of Dupuis et al. (1992, 1993). Small deviations can
be observed for the abundance ratios in some objects. This could indicate
non-solar metal-to-metal ratios in the accreted material. Hydrogen can be
detected in virtually all of our objects. However, its average accretion rate
must be at least two orders of magnitude lower than the metal accretion rate.
