  Using 13.4 $fb^{-1}$ of data collected with the CLEO detector at the Cornell
Electron Storage Ring, we have observed 300 events for the two-photon
production of ground-state pseudo-scalar charmonium in the decay $\eta_c$ ->
$K_S K^{\mp} \pi^{\pm}$. We have measured the $\eta_c$ mass to be (2980.4 +-
2.3 (stat) +- 0.6 (sys)) MeV and its full width as (27.0 +- 5.8 (stat) +- 1.4
(sys)) MeV. We have determined the two-photon partial width of the $\eta_c$
meson to be (7.6 +- 0.8 (stat) +- 0.4 (sys) +- 2.3 (br)) keV, with the last
uncertainty associated with the decay branching fraction.
