  We present the first significant detection of relativistic smearing of the
X-ray reflection spectrum from the putative accretion disk in the low/hard
state of Cyg X--1. The ionization state, and amount of relativistic smearing
are simultaneously constrained by the X-ray spectra, and we conclude that the
disk is not strongly ionised, does not generally extend down to the last stable
orbit at 3 Schwarzschild radii and covers rather less than half the sky as seen
from the X-ray source. These results are consistent with a geometry where the
optically thick disk truncates at a few tens of Schwarzschild radii, with the
inner region occupied by the X-ray hot, optically thin(ish) plasma. Such a
geometry is also inferred from previous studies of the reflected spectrum in
Galactic Black Hole transient sources, and from detailed considerations of the
overall continuum spectral shape, suggesting that there is some robust
instability which disrupts the inner accretion disk in low/hard state Galactic
Black Holes.
