came upon a submerged forest.

In that old time of the great sea that covered the globe, we are told
that there was a dense atmosphere over the face of the deep. So things
were shaping themselves for the far-off time when life should exist,
not only in the sea, where the first life did appear, but on land. But
it took millions of years to fit the earth for living things.

The cooling of the earth made it shrink, and the crust began to be
folded into gentle curves, as the skin of a shrunken apple becomes
wrinkled on the flesh. Some of these creases merely changed the depth of
water on the sea bottom; but one ridge was lifted above the water. The
water parted and streamed down its sloping sides, and a granite reef,
which shone in the sunshine, became the first dry land. It lay east and
west, and stretched for many miles. It is still dry land and is a part
of our own continent. Now it is but a small part of the country, but it
is known by geologists, who can tell its boundaries, though newer land
joins it on every side. It is named the Laurentian Hills, on geological
maps. Its southern border reaches along the northern boundary of the
Great Lakes to the head-waters of the Mississippi River.

From this base, two ridges are lifted, forming a colossal V. One extends
northeast to Nova Scotia; the other northwest to the Arctic seas. The V
encloses Hudson Bay.

Besides this first elongated island of bare rocks, land appeared in a
strip where now the Blue Ridge Mountains stretch from New England to
Georgia. The other side of the continent lifted up two folds of the
crust above sea level. They are the main ridges of the Colorado and the
Wasatch Mountains. Possibly the main ridge of the Sierra Nevada rose
also at this time. The Ozark group of mountains, too, showed as a few
island peaks above the sea.

These first rocks were rapidly eaten away, for the atmosphere was not
like ours, but heavily charged with destructive gases, which did more,
we believe, to disintegrate the exposed rock surfaces than did the two
other forces, wind and water, combined. The sediment washed down to the
sea by rains, accumulated along the shores, filling the shallows and
thus adding to the width of the land areas. The ancient granite ridge of
the Laurentian Hills is now low, and slopes gently. This is true of all
very old mountains. The newer ones are high and steep. It takes time to
grind down the peaks and carry off the waste material loosened by