This stone spiral is not, as the people of Arkansas once maintained, a corkscrew used by the devil, but the filled-in burrow of an ancient kind of beaver - and fossil hunters proved that by excavating this one which had the chamber at the very bottom still preserved, and in it the bones of the animal that made it. This is not the devil's toenail, it's an early ancestor of today's oyster. A thunderbolt? No, the internal skeleton of an animal like a squid which had tentacles at one end and as we now know, two internal gills. Stone snakes? No. Shells from a long-vanished sea. Such revelations are, operhaps, even more astonishing than the myths people invented to explain the strange shapes they found in rocks.