Kelleys Island stands high because it is a piece of the structural arch. While the Wisconsinan ice sheet was excavating the Great Lakes, reaming out whole networks of streams and carrying away the prominent features of their valleys, it bevelled but could not destroy the resistant structural arch. An engulfed ridge stood up from the bottom of the primal lake. With the weight of the ice gone, all of northern America slowly rebounded. A large part of the water gradually drained away, leaving Kelleys Island dry in the air, sixty feet above the level of Lake Erie. We passed the island cemetery, its names recorded in limestone. We came to the north shore, where the beginnings of a quarrying operation had revealed how the ice had cut its kantoor per uur almere tracks into the rock. “GLACIAL GROOVES STATE MEMORIAL.” It was as if a giant had drawn his fingers through an acre of soft butter. The grooves were parallel. They were larger than the gutters of bowling lanes. Aggregately, they suggested the fluted shafts of Greek columns. Their compass orientation .was n01theast-southwest -the established glide path of the moving ice. Nowhere had we seen or would we see more emphatic evidence of continental glaciation, with the obvious exception of the Great Lakes themselves. “If you were to hydraulically flush northern Ohio-wash off the soil from the bedrock-you’d see a hell of a lot of these grooves,” Anita said. “In several hundred years, these won’t be here. Limestone is soft enough to be grooved and hard enough to resist weather for a few hundred years. In shale, grooves like these would go quickly. The ice, carrying boulders in its underside-carrying those amphibolites and red jaspers in the people’s houses-tore the hell out of this island. When Agassiz saw things like this, he went bananas.” There have been kantoor per uur amsterdam glacial geologists, even in the late twentieth century, who have believed that such impressive grooves were gouged by boulders rolling in the Flood. Exceptions notwithstanding, Louis Agassiz’s theory of continental glaciation, like the theory of plate tectonics, achieved with extraordinary swiftness its general acceptance in the world. As Thomas Kuhn has demonstrated in The Structure of Scientific Revolutions, when a novel theory becomes relatively established it defines the patterns of amplifying research for many years and even centuries-until a new theory comes along to overturn the old, until an Einstein appears, outreaching the principles of Newton. Conceivably, the theory of plate tectonics will one day experience a general reformation.