  New spectroscopic observations (R=15000 and 40000) are given for 31 nearby (V
< 11) BHB star candidates. IUE low-resolution spectra are available for most of
them. New determinations of temperature, gravity, reddening and abundances were
obtained from these data using models computed by Castelli with an updated
version of the ATLAS9 code. A summary of the visual photometry for these stars
(including new photometry obtained at Kitt Peak) is also given. All 31
candidates are halo stars. We classify 28 as BHB stars because: (1) They lie
close to the ZAHB (in a similar position to globular cluster BHB stars) in the
Teff vs. log g plot. (2) Their distribution of vsini (less than 40 km/s) is
similar to that found for the BHB stars in globular clusters. (3) Their [Fe/H]
lies between -0.99 and -2.95 (mean [Fe/H] -1.67, dispersion 0.42 dex) which is
similar to that found for field halo RR Lyrae and red HB stars but more metal-
poor than for halo globular clusters. Field BHB stars with Teff greater than
8500 K show the He I (4471 A) line corresponding to solar abundance. (4) They
show a similar average enhancement of the alpha-elements ([Mg/Fe] = +0.43 +/-
0.04 and [Ti/Fe] = +0.44 +/- 0.02) to that found for other halo field stars of
similar metallicity. Comments are given on a further 25 stars that have
previously been suggested to be BHB stars; these were not included in our
sample because they did not fulfil one or more of the above criteria.
