  A new set of very high signal-to-noise (S/N > 100/1), medium-resolution
(R~3000) optical spectra have been obtained for 302 of the candidate
"weak-metal" stars selected by Bidelman & MacConnell. We use these data to
calibrate the recently developed generalization of the SEGUE Stellar Parameter
Pipeline, and obtain estimates of the atmospheric parameters (Teff, log g , and
[Fe/H]) for these non-SDSS/SEGUE data; we also obtain estimates of [C/Fe]. The
new abundance measurements are shown to be consistent with available
high-resolution spectroscopic determinations, and represent a substantial
improvement over the accuracies obtained from the previous photometric
estimates reported in Paper I of this series. The apparent offset in the
photometric abundances of the giants in this sample noted by several authors is
confirmed by our new spectroscopy; no such effect is found for the dwarfs. The
presence of a metal-weak thick-disk (MWTD) population is clearly supported by
these new abundance data. Some 25% of the stars with metallicities -1.8 <
[Fe/H] <= -0.8 exhibit orbital eccentricities e < 0.4, yet are clearly
separated from members of the inner-halo population with similar metallicities
by their location in a Lindblad energy vs. angular momentum diagram. A
comparison is made with recent results for a similar-size sample of RAVE stars
from Ruchti et al. We conclude, based on both of these samples, that the MWTD
is real, and must be accounted for in discussions of the formation and
evolution of the disk system of the Milky Way.
