John Muir,
The Grand Cañon of the Colorado
“ But far the greater part of the plateau is good sound desert, rocky, sandy, or fluffy with loose ashes and dust, dissected in some places into a labyrinth of stream-channel chasms like cracks in a dry clay-bed, or the narrow slit crevasses of glaciers, — blackened with lava-flows, dotted with volcanoes and beautiful buttes, and lined with long continuous escarpments, — a vast bed of sediments of an ancient sea-bottom, still nearly as level as when first laid down after being heaved into the sky a mile or two high. ”
