  Critical properties of the Calogero-Sutherland model of $BC_N$-type
($BC_N$-CS model) are studied. Using the asymptotic Bethe-ansatz spectrum of
the $BC_N$-CS model, we calculate finite-size corrections in the energy
spectrum. Since the $BC_N$-CS model does not possess translational invariance,
the finite-size spectrum acquires the contributions coming from ``boundaries''.
We show that the low-energy critical behavior of the model is described by
$c=1$ boundary conformal field theory. Thus the universality class of the model
is identified as a chiral Tomonaga-Luttinger liquid.
