The kayak slips through slate-gray water, so still this morning that the only movement comes from the pull of the paddle, the only sounds from an occasional bird trill or cricket chirp. I am at the western edge of a lake whose shape resembles a sea serpent on topographical maps. To my left, several scraggly trees shelter a dusty picnic area; to the right, columnar basalt cliffs rise in two tiers above the water. The prow of the kayak points toward the length of the two-mile lake, nudging through shallow water surrounding a small island. Beyond, the view opens up to the half-mile-wide, twenty-foot-deep body of the sea serpent. Walls of variegated brown basalt enclose the water and reflect a reverse image on its surface.