  We present results for the spectrum of b-bbar bound states in the quenched
approximation for three different values of the lattice spacing, in the range
0.05fm to 0.15fm. We find our results for spin-independent splittings in
physical units to be independent of the lattice spacing, indicating the absence
of systematic errors from discretisation effects. Spin-dependent splittings are
more sensitive to the lattice spacing and higher order corrections to the
action; we discuss the size of these effects and what can be done to arrive at
a physical result.
