  We present linear polarization in the V band for 77 stars in the field of the
globular cluster 47 Tucanae (NGC 104), and for 14 bright-star-free regions,
located along an elliptical isophotal contour of the cluster, as well as UBVRI
measurements for the cluster nucleus. The observations show variable foreground
polarization that, once removed, leaves marginally significant polarization
residuals for the non-variable bright red giants. Although these residuals are
small there is, however, a systematic trend in the sense that the larger ones
are seen towards the south of the cluster (in a direction opposite to that of
the cluster proper motion). In contrast, most of the variable stars do show
significant intrinsic polarization. The behavior of the star-free regions is
similar to that of the non-variable stars and sets an upper limit to the
possible existence of a global pattern of scattered (and polarized)
intra-cluster light in the V band. In turn, the multicolor observations of the
cluster nucleus cannot be fitted with a Serkowski law and exhibit a
polarization excess both in U and B. This polarization could be explained as a
combination of the foreground interstellar component and another one arising in
dust located in the nucleus and illuminated by a bright blue post-AGB star (at
48" from the cluster center). An inspection of a set of archive HST WFPC2
images reveals the presence of a number of dark patches in the innermost
regions of the cluster. A prominent patch (some 5" by 3" in size) located at
12" from the cluster center and with a position angle (N to E) of 120 degrees,
has a slightly different polarization, compared to that of the cluster nucleus,
and appears as a good candidate to be identified as a dust globule within the
cluster.
