  The $B_s$ system is analyzed in light of a possible width difference
$\Delta\Gamma_s$ between its mass eigenstates. If $\Delta\Gamma_s$ is sizable,
untagged $B_s$-meson decays may allow a probe of CP violation and moreover the
extraction both of the Wolfenstein parameter $\eta$ and of the notoriously
difficult to measure angle $\gamma$ of the unitarity triangle. To accomplish
this ambitious task, time-dependent angular distributions for untagged $B_s$
decays into admixtures of CP eigenstates and channels that are caused by $\bar
b\to\bar c u\bar s$ quark-level transitions play a key role. The work described
here was done in collaboration with Isard Dunietz.
