Union County courier. [volume] (Elk Point, Union County, D.T. [S.D.]) 187?-1913, 1888-03-21
The Ice Age In North America.

Important discoveries have been
made during the last few years. The
field Of glaciation is very extensive, in
Sweden, those Of central Europe, New
Zealand, and the whole Antarctic con-
tinent. Some Of these glaciers are on
o colossal scale, as one at Spitzbergcn,
which is 800 feet high and 1000 feet
across. But these are only remnants of
former glaciers which filled the North
Sea as far down as the Isle of Man.
The Scandinavian glaciers extended
down to Dresden and the Hartz Noun
taina They then swept eastward
across Poland and into Russia, cover-
ing l, 700 900 kilometers, of Europe to
q depth of {, 1000 or 1000 feet The i'm
mense ice field encircling the South
ern Pole $500 miles in diameter.
From this feels icebergs are continu-
ally breaking off and floating north
ward.
The glaciated region of North Amer.
lea was far larger than hat OF Europe.
1t covered all of New England, the
southern limit passing through Nan
tucket, Martha's Vineyard, and Block
Island. The region covered by New
York City and Brooklyn was all enyel-
oped in ice. Bnt this was near the
southern limit, which struck New Jer-
sey at Perth Amboy, went up to Nor
ristown and then crossed to Belvidere.
It covered q small part of Pennsylva-
mia, turned north into New York, then
southwestward into Pennsylvania and
nm - Ahn (hs4 psxynH ~vhsr1, "a SoI1z--Y
about 100 miles, by Cincinnati, down
nearly to Louisville. A triangular por-
ton Of Ohio was left unglsciated. In
Illinois the ice extended down to lati-
tude 80, and crossed the Mississippi
River neal St Louis. It crossed Mis-
souri, to Kansas City, then on across
Nebraska, up to the Yellowstone, on
westward forty miles above Fort Ben.
ton, and $50 on to the Pacific Ocean.
This outline gives US q good idea of
the southern limit of the ice field in
this country.
The Aus OF glaciers--Glaci regions
can be easily recognized. Ice cannot
adapt itself to the country a. water
can lce-felds move slowly, somewhat
$ semi-fuids do. The stones under.
meath are dragged along and scratched
(striated), the ice acting on these rocks
IS . rasp. These scratched stones
show the action of glaciers, and the
longest diameters of these stones is
found in line with the glacier. This is
NOT always o certain sign, as stones may
be striated by loose icebergs or by land.
slides. Water deposits are always
stratified; ice deposits are not. A
food deposits pebbles and even stones,
but low water only mud. The ice
leaves the coarse and fine deposits oil
mingled together, while water, acting
rs . sieve. separates and stratifes
them. Pebbles are polished and
scratched by glacial action. The con-
tour Of she glacial boundry is both ser
rate and crenate. The boundary of the
glacial deposits forms . nearly straight
line over the hills and valleys.
What was the depth OF ice accumu'
lated during the glacial period? Mt
Desert Island was completely covered,
the ice being, therefore, over ], 800 feet
deep. A boulder was taken from
within twenty-five feet of the summit
Of Mt Washington and carried . long
distance. Monadnock was completely
covered. New England was, therefore,
from . half to . whole Of . mile under
the ice. It was probably half . mile
deep in the Mohawk Valley, and q
deep al over the Great Lakes. Ice
bergs are seven or eight feet under
water tor each foot above. Yet Ice
bergs have been seen from 400 10 soc
feet ont Of the water, and from 1000
test 10 two miles long. The ice vas,
! tkerefore. several thousand feet deer,