  Bent-double radio sources can act as tracers for clusters of galaxies. We
present imaging and spectroscopic observations of the environments surrounding
ten of these sources (most of them Wide Angle Tails (WATs)) selected from the
VLA FIRST survey. Our results reveal a previously unknown cluster associated
with eight of the radio sources with redshifts in the range 0.33 < z < 0.85;
furthermore, we cannot rule out that the other two bent doubles may be
associated with clusters at higher redshift. Richness measurements indicate
that these clusters are typical of the majority of those found in the Abell
(1958) catalog, with a range of Abell richness classes from 0 to 2. The
line-of-sight velocity dispersions are very different from cluster to cluster,
ranging from approximately 300 to 1100 km/s. At the upper end of these
intervals, we may be sampling some of the highest-redshift massive clusters
known. Alternatively, the large velocity dispersions measured in some of the
clusters may indicate that they are merging systems with significant
substructure, consistent with recent ideas concerning WAT formation (Burns et
al. 1994).
