  Using the Chandra High Energy Transmission Grating Spectrometer (HETGS), we
have found significant absorption features in the X-ray spectrum of Cyg X-1
taken in the continuous clocking mode. These features include resonance lines
of He-like ions of S, Si, and Mg; the Ly alpha lines of H-like S, Si, Mg, and
Ne; and several lower ionization lines of Fe XX, XXII, and XXIV. Preliminary
analysis shows that the lines are resolved in many cases, giving line widths of
order 300 km/s and are redshifted by 460 +/- 10 km/s. These features are
interpreted in the context of an accreting stellar wind model that is ionized
by the X-ray source. In addition, there are clear absorption features due to
neutral Mg, Fe, and O in the interstellar medium.
