The Somerset herald. [volume] (Somerset, Pa.) 1870-1936, 1876-01-05

Hsruer's Ferry. CT has e indeed
any ono Of the numerous gaps made
BIZ seaward lowing rivers through
the long mountain ridges which flank
the Allegheaies, must have been
s,rack By the question hcw 8 eompsr-
~alively small stream could overcome
90 Formidable al obstruction
Evidently The river could not have
tsken advantage Of q natural cleit or
assure through the mountain dam,
for The Strata correspond in The oP-
posing sides Of The esp, and the nver
flows over an uabrokeH stratum IN
der-ranniBg The broken slrsis Of the
banks. The gap as plsinly denotes a
section cut cut IF the mountain as s.
notch il G stick does The removal Of
the wood The disconnected edges
Of the Strata tell precisely the same
story SIS The several lines Of annual
growth on TIE sides Of a wood chop
per's cut; the connecting portions OF
woJd aud stone have been removed.
TIE question Is: How!
The first and most natural supp0-
sii;on would be that the valley, back
Of the dam, had originally been fill
ed. forming a lake whose outlet was
over the ridge above the present riv-
er channel and that as the outlet
was lowered bv the wearing down OF
the obstruction, the lake was drained
until the entire valley was laid bare.
This superstition is negatiFed By The
plain fact that it would be impossl-
bic to fill the valley to the height of
the ridge at the point of the gap
Before the water could reach that
level it would fnd an outlet else
where, where the natural %elevation
Of the dam was less. An excellent
illustration occurs . few miles above
Harrisburg, where the Susqnehanna
crosses a 1exure Of the mountain
ridge, cutting twice through the
mountains within a few miles, when
apparently it might easily have
avoided the obstruction by going q
few miles around.
Another supposition Is that origl-
naIly the river ran at q level cores
ponding with the top Of the ridge,
and that the present valley through
which il runs is the result Of erosion ;
while the river was slowly wearing
through the bard mountain strata,
the softer earth Of the surrounding
country was washed away through
itg sinking channel, leaving the more
u~nvielding rocks IN mountain ridges.
From this point Of view, the river Is
to be regarded not merely as the
~cleayer of the mountain barrier but
as the Greater Of it, by reducing the
level Of the adjacent land.
Hitherto this s%upposition has been
the most plausible and the most gen
orally accepted. But another and,
perhaps, truer explanation is suggest
ed by Prof. Powell's Exploration of
the Canyons Of the Colorado"
As opr Atlantic rivers cut through
the Allegheny ridges, so the Green
river, the chief head stream of the
Colorado, pierces the Uinta noun
tains, flowing through a series ofcan-
yons compared with which our east
ern water gaps are Insignificant. As
10 the case of the Susquehan.a,
above noted, the river bursts through
the opposing mountains when appa-
rently it might have found an easier
passage by going round them. Why
did it choose the harder course!
Prof. PJwell's answer is that it
bad the right of way. 1t was run
ming there before the mountains were
formed and simply removed the OBJ
struction as fast as it rose in the
way.
The contraction OF the earth causes
the strata near the surface to wrinkle
or fold. and such q fold was started
athwart the course of the stream
now Known at Green river. Had
the fold been suddenly formed, 1t
would have been an obstruction suf-
6cient to turn the water into a new
course, TO the east, beyond the ex-
%tention of the wrinkle; but the emer-
gency Of the fold above the general
surface Of the country was little if
any faster than the progress of the
corrosion of the channel. We may
say then, that the river did not eat
its way down through the mountains,
from o height of many thousand feet
above its present site; but having an
elevation, differing but little perhaps
from what it now has, as the fold
was lifted, it cleared away the OBJ
struction by cutting a canyon, and
the walls were thus elevated on either
side. The river preserved its level,
but the mountains were lifted up, as
the saw r%evolves on a fixed point as
the log through which it cuts is NOV
ed along. The river was the saw
which cut the mountains in two"
The gigantic nature of the aqueous
saw cut can be family estimated
from the circumstance that the noun
tain log or field bad a diameter Of fifty
miles, while the depth of the cut,
that is, the elevation of the fold above
the present level Of The river, was
over twenty-four thousand feet. But
a fraction of this enormous uplift Of
rock remains. As the rocks were
lifted, rains fell upon them and gath
cred into streams, and the wash of
the rains and the corrosion of the
rivers cut the fold down almost as
fast as it rose, SO that the present al
titude of the Uintas marks only the
difference between the elevation and
the denudation. The mountains were
not thrust up as peaks, but o great
block was slowly lifted, and from
this the mountains were carved by
the clouds-patient artists, who take
what time may be necessary for their
work.-Scientifc american.
9 6 ,OO0, 900 In Eggs.
Three fraiqht cara containing Il =