The Vancouver independent. (Vancouver, W.T. [Wash.]) 1875-1910, 1880-04-15

In a recent lecture before the San
Francisco Academy of Sciences, Major
Powell, of the United States Geologi-
cal Survey, spoke of the great Colorado
river:
The lower third of Colorado, he said,
lies but little above the level of the
sea, while the upper twO-thirds has an
elevation of from 1000 to 5000 feet
Out of this basin or plateau rises the
snOw-clad mountains to an altitude of
from 10000 to II 900 feet. Hardlyany
rain falls upon this upper basin of
mountains, but in winter immense
drifts of snow cover these eternal
rocks. When in summer the snow
commences to melt ten thousand cas-
cades and little streams are formed.
They plunge down the rocky sides of
the mountains, cut their course down
through the immense plateaus, and
gradully run as swift rivers through
the silent region. They cut deep chan
nels through the rocks, 80 that the
beds of these rivers are variously from
500 to 700 feet below the general sur
face of the plateaus.
For 200 miles the Green and Grand
rivers run in Il channel cut to mile
in depth. The whole uppertwo-thirds
of Colorado is cut up by gorges and
canyons, so that the country is almost
impossible. There are no evidences
that these canyons are formed by up
heavals of huge masses of rocks, but
they are all caused by the slow but
perpetual action of the mountain
streams. If $50 mountains like Mount
Washington were plucked up by the
root they would not fill the Grand
canyon of the Colorado river. The
fall of the river Is very great, and dif-
fers from % to POO feet per mile; it is
therefore not navigabie.
Moreover, for 1000 miles along the
Colorado river there is no place where
town or farm could be located, for
the river is entirely unapproachable
forthat distance. These canyons have
carried away vast areas of sediment |
The whole region has become one of
naked rocks. Geological studies can
here he made with certainty: every
stra atpm eau, be. meaSlued,vNN 'i.se
amount of material carried away by
this river is as large as a rock 600 feet
in depth covering the states of New
York, Pennsylvania, Ohio and Indi-
ana, or large rs California and Ne
vada. This vast amount of rock the
storms of ages have hurled off.
The rivers of Colorado are older than
the valleys and mountains. Grad
ually, rs the mountains rose, the riv-
ers cut their way through them. The
stratification of these rocks is never
sweeping, but always vertically bro
ken, rising or falling abruptly from
100 to 1900 feet. These strata are al
ways horizontal, and sometimes there
ar, found zones of rocks 20 miles in
width, broken into irregular frag-
ments. The Colorado river carries
about rs much water as the Ohio at
Louisville.
Where the rock is soft. it forms a
broad, wide river, but when it passes
through basalt its channel is narrowed
down to 60 or 20 feet, and through II
this vast volume of water plunges and
rushes i'm a mad, wild, and irresistible
stream, that would carry anything be-
fore it. Sometimes, when storm
arises and heavy showers fall, this
mile deep channel of the river is filled
in an incredibly short time to a height
of hundreds of feet, and the torrent
sweeps through it at n most terrific
rate There are, however, no vertical
falls of any magnitude in the Colorado
river
Most interesting to the explorers are
the thousand of ancient ruins through
out the whole region. These habita-
tions are built of fstone, and often reach
height of seven stories. At the
heads of the streams forming the Col
orado are the most ancient of these
ruins, while farther down in the deep
cliffs and canyons they apparently
belong TO laterperiod. Itseems that
the people were driven from the beau
tiful valleys above to seek protection
on these high cliffs, which were better
adapted for defense. The major en-
tered into a general explanation OF
stone implements found among these
ruins. His remarks throughout re-
ceived the closest attention of the au-
dience.