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.
Walking quietly about in the alleys and byways of the Grand Canon City,
we learn something of the way it was made; and all must admire effects so
great from means apparently so simple: rain striking light hammer-blows
or heavier in streams, with many rest Sundays; soft air and light, gentle
sappers and miners, toiling forever; the big river sawing the plateau
asunder, carrying away the eroded and ground waste, and exposing the
edges of the strata to the weather; rain torrents sawing cross-streets
and alleys, exposing the strata in the same way in hundreds of sections,
the softer, less resisting beds weathering and receding faster, thus
undermining the harder beds, which fall, not only in small weathered
particles, but in heavy sheer-cleaving masses, assisted down from time to
time by kindly earthquakes, rain torrents rushing the fallen material
to the river, keeping the wall rocks constantly exposed.
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