The Cairo bulletin., 1914-05-18
BIRTH OF A RIVER
As Land Shrank Bed of ST. Law.
renee Was Formed.
Required Ages of Straining, Cracking
and Shrinking Of the Earth. To-
gether With Earthquakes, Sun
and frcst TO Form Channel.

Try to think of a time when the
earth was covered by a mass of water.
hot. steaming and often tremendously
| disturbed by the throes of a globe be-
heath 1t that was shrinking because
II was becoming cooler. says the
Youths Companion AS the globe
| shrank, every particle OF the outside
was naturally pulled in toward the
center and the hardening crust, which
could not be packed any more solidly
than 1t was. had TO wrinkle, sinking
down here and bullying up somewhere
else. After time certain of these
rising wrinkles, or folds. the thicker,
or hrmer, parts OF the earth's crust.
stood the strain and became perma-
hent ridges. The Oldest of them THAI
biologists know, and apparently the
hrst that bulged up above the univer-
sal ocean and remained high and dry
was the broad mass on which Canada
now rests. 1t is part of the original
crust OF the earth, and We can see il
today, wherever it is not covered By
newer rocks or soil, just as it crystal
lied and cooled out OF the primevai
molten material
Ihis mass formed a broad Y from
Labrador down to Lake Huron, and
thence northwestward to Alaska; on
account of its shape biologists call it
the Canadian shield. 1t is the oldest
land known and apparently the strong
est. for there are no signs OF any ex-
tensive changes in 1t Except the wear.
ing away of the surface) since 1t first
rolled the ocean off its shoulders.
OF the eastern coast Of this primi-
tive continent lay chain Of lofty
islands, about on the line Of the Blue
Ridge, the White mountains, the Maine
coast and Nova Scotia Between these
islands and the mainland was trough
like space that ran from western Que
bee southwestward to Ohio. 1t was
two or three hundred miles wide and
filled with shallow sea, and just out
side the island chain was the great
hollow that held the Atlantic ocean.
Time went on. For ages the strain
ing and cracking of the shrinking
globe, earthquakes. sun and frost
pounding surf. running water. blowing
gales, etc.--all labored to tear down
the mountains and carry the wreckage
Of rocks and dust away into the val
leys and seas. In this way vast
masses OF rock, in layers of shales.
sandstones and what not, were laid
down in that narrow. troughlike sea
between the chain OF islands and the
continent. All these "sedimentary"
rocks were soft and weak. as com
pared with the solid old GRANTEES deep
the trough itself, sagging fold was
line of weakness in the crust AS the
load Of deposits became heavier and
heavier, the floor of this trough slowly
yielded and as 1t sank toward the
heated region below the under side
melted and grew thinner and thinner,
This could not go on forever, and
soon the continual shrinking of the
globe and the enormous pressure of
the weight Of the ocean became ire
sistible. The Canadian shield was i'm
movable, so the rock In the trough be-
gan to bulge or crumple all along its
length. Gradually, not all at once, but
by slow and varying movements. those
folds were squeezed up. which IN their
broken and worn down forms we know
as the Appalachian mountains.
Toward the south there was room
for this action TO be rather gentle and
regular, but in the far northeast the
trough was narrow and the soft rocks
were set on edge, overturned and
splintered against the solid continent
Very early in the struggle a great frac-
ture of the earth's crust occurred here
along a curving northeast and south
west line 1t left deep and broad
trench between the crushed and dis
placed rocks of the trough and the
granite shore Of the Canadian shield
Into this trench rushed all the interior
waters Of the continent, draining away
to the sea, and the st. Lawrence river
was born! There. no doubt. 1t will re-
main as long as the earth keeps its
present form.
At that time there was no Gulf of
st. Lawrence, The land extended out
to a coast line that stretched unbroken
from Nova Scotia to Labrador. The
present gulf is the result of sinking
of the coast region. Most of it is very
shallow, but a chart of soundings
shows the ancient river bed as chan
mel winding out between Newfound
land and Cape Breton to the deep
ocean.