  We have measured the muon flux and production rate of muon-induced neutrons
at a depth of 611 m water equivalent. Our apparatus comprises three layers of
crossed plastic scintillator hodoscopes for tracking the incident cosmic-ray
muons and 760 L of gadolinium-doped liquid scintillator for producing and
detecting neutrons. The vertical muon intensity was measured to be $I_{\mu} =
(5.7 \pm 0.6) \times 10^{-6}$ cm$^{-2}$s$^{-1}$sr$^{-1}$. The yield of
muon-induced neutrons in the liquid scintillator was determined to be $Y_{n} =
(1.19 \pm 0.08 (stat) \pm 0.21 (syst)) \times 10^{-4}$
neutrons/($\mu\cdot$g$\cdot$cm$^{-2}$). A fit to the recently measured neutron
yields at different depths gave a mean muon energy dependence of $\left\langle
E_{\mu} \right\rangle^{0.76 \pm 0.03}$ for liquid-scintillator targets.
