hrough mountain limestone to a depth
of 6000 feet. The strata are horizontal, and the whole series has been
cleared away by the continued erosive power of water, aided by gravel
and boulders. This work has been going on from the commencement of the
period in the world's history known as the Pliocene Age, and it is
reckoned that the interval which must have elapsed since then must have
amounted to millions of years. And yet this space of time, from the
Pliocene Age to our own, must, geologically speaking, be extremely
insignificant compared to the length of the great geological periods.
The six thousand years which we call the historical period is but the
beat of a second on the clock of eternity, and what the historian calls
primeval times is the latest and most recent period in the last of all
the geologist's ages. For while the historian deals with revolutions of
the sun of only 365 days, the geologist is only satisfied with thousands
and millions of years. The Colorado River has presented him with one of
the standards by which he is able to calculate lapse of time. You will
acknowledge that it is no small feat for running water to cut its way
down through solid rock to a depth of 6500 feet; and these canons are
more than 180 miles long and four to eleven miles broad.

"By its work here the river has sculptured in the face of the earth a
landscape which awes and astonishes the spectator. It is like nothing
he has ever seen before. When he stood at the foot of the Alps he gazed
up at the snow-clad wastes of the mighty mountain masses. When he stands
at the edge of the canons of the Colorado he looks down and sees a
yawning chasm, and on the other side of the giddy ravine the walls rise
perpendicular or sloping. He seems to stand before the artistically
decorated facade of a gigantic house or palace in an immense town. He
sees in the walls of the valley, niches and excavations like a Roman
theatre, with benches rising in tiers. At their sides stand gables and
projections of rock, like turrets and buttresses. Under huge cornices
rise columns standing out or attached at the back, all planned on the
same gigantic scale. The precipitous cliffs are dark, and the whole
country is coloured in pink, yellow, red, and warm brown tones. The sun
pours its gold over the majestic desolation. No grassy sward, no
vegetation carpets the horizontal or vertical surfaces with green. Here
and there a pine leans its crown over the chasm, and