THE DIVINE ABYSS 
The next step, or platform, the Cretaceous, slopes 
down gradually or dies out on the step beneath it; 
then comes the Jurassic, which ends in white sand- 
stone cliffs several hundred feet high; then the 
Triassic, which ends in the famous vermilion cliffs 
thousands of feet high, most striking in color and in 
form; then the Permian tread, which also ends 
in striking cliffs, with their own style of color and 
architecture; and, lastly, the great Carboniferous 
platform in which the cafion itself is carved. Now, 
all these various strata above the ‘cafion, making 
at one time a thickness of over a mile, were worn 
away in Pliocene times, before the cutting of the 
Grand Cafion began. Had they remained, and been 
cut through, we should have had a chasm two miles 
deep instead of one mile. 
The cutting power of a large, rapid volume of 
water, like the Colorado, charged with sand and 
gravel, is very great. According to Major Dutton, 
in the hydraulic mines of California, the escaping 
water has been known to cut a chasm from twelve 
to twenty feet deep in hard basaltic rock, in a single 
year. This is, of course, exceptional, but there have, 
no doubt, been times when the Colorado cut down- 
ward very rapidly. The enormous weathering of its 
side walls is to me the more wonderful, probably 
because the forces that have achieved this task are 
silent and invisible, and, so far as our experience 
goes, so infinitely slow in their action. 
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