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Washburn
Report Index
YELLOWSTONE EXPEDITION OF 1870
Page 17
there are a dozen caldrons of grayish clay mud,
varying from 6 to 40 feet in diameter, and from 3 to 10 feet in depth, each
with its vent of sulphur vapor and slimy crater, from 3 to 5 feet in height.
Just above camp the bed of the river is full of hot-water spouts, with
bubbles of gas escaping. In a ravine, over the ridge, hot vapors pour out in
every direction, and here is a remarkable group. A small stream of green
water flows down the ravine, having its source in a rocky cave in the bank,
with an aperture of 6 by 8 feet -- a perfect grotto, lined with brilliant
metallic tints of green, red, and black, from which steam escapes in regular
pulsations to a distance of 40 feet, forcing out the water in waves, which
break over an outside horizontal rim, about once in ten seconds. A few yards
further down are several boiling springs of yellow muddy-water, the largest
of which is 80 feet in diameter, through which the vapor rushes with a loud
hissing sound. One hundred yards from the bank of the river, and below these
springs, is a geyser of dark muddy water; its basin is 200 feet across on
the outer rim, and about 6 feet deep, with a channel cut through one side
for the passage of flood water from the hills. The area is floored with a
strata of mud rock, deposited from the water, forming a circular plateau, in
the middle of which is an oblong crater, 45 by 75 feet, with an irregular
vapor vent, and system of steam jets adjoining, covering the whole space to
the outer rim on the right. This was a periodic geyser, having eruptions
every six hours, and in the following manner: The crater being full of
boiling water, and the vapor vent active, suddenly columns of steam shoot up
through the water to the height of 300 feet. The ground trembles, the vapor
hisses through the vent with increased force. The water of the crater is
violently agitated, being thrown up in vast columns, to the height of 30 and
40 feet, splashing out as far as the rim of the basin with great force. This
continues for half an hour, the water increasing in quantity in the crater
all the while. Then the steam ceases suddenly to escape, the water settles,
and commences to lower in the crater, continuing to fall to the depth of 35
feet, leaving bare the incrusted and funnel-shaped walls, which converge at
that depth to the diameter of 7 feet. The water here stands for a time, the
steam jets cease to hiss, the vapor vent to give forth its fumes, and all is
quiet. After the lapse of an hour, the water stoutly rises again, the vents
become active, and at the end of the regular period the whole performance is
repeated as before.
A few hundred yards from here is an object of the
greatest interest. On the slope of a small and steep wooded ravine is the
crater of a mud volcano, 30 feet in diameter at the rim, which is elevated a
few feet above the surface on the lower side, and bounded by the slope of
the hill of the upper, converging, as it deepens, to the diameter of 15 feet
at the lowest visible point, about 40 feet down. Heavy volumes of steam
escape from this opening, ascending to the height of 300 feet. From far down
in the earth came a jarring sound, in regular beats of five seconds, with a
concussion that shook the ground at two hundred yards distant. After each
concussion came a splash of mud, as if thrown to a great height; sometimes
it could be seen from the edge of the crater, but none was entirely ejected
while we were there. Occasionally an explosion was heard like the bursting
of heavy guns behind an embankment, and causing the earth to tremble for a
mile around. These explosions were accompanied by a vast increase of the
volumes of steam poured forth from the crater. This volcano has not been
long in operation, as young pines, crushed flat to the earth under the rim
of mud, were still alive at the tops. The amount of matter ejected was not
great, con-
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