When the earth was in a state of fiery fluidity, all of the water it
now contains was suspended at a great distance above it. Beside the
oceans which now cover three-fourths of the surface of the globe, rocks
and coals contain from ten per cent to one half water, all of which was
primarily held in suspension. The bosom of the earth is continually
absorbing water as is demonstrated by deep mines and other excavations.
Dana estimates that even if the crust of the earth is but five miles
thick that the oceans would be 400 feet deeper if all of the earth’s
imbibed waters could be returned to them. But the earth’s crust is more
likely to be 100 miles thick, and it has been imbibing these waters
for millions of years if not millions of ages. This would increase the
oceans to about 8000 feet deeper than now. Yet oceans are much deeper
today than they were in geologic times.
This great mass of vapor would rotate by centrifugal force at the
equator, but there being no such force at the poles it was there kept
from falling by heat alone. If the earth had not rotated the vapors
would have occupied great heights; but centrifugal force being aided by
actual rotation they were driven much farther. These forces necessarily
drove the vapors over the equator. If, however, any vapors were left at
the poles they must have fallen when the earth cooled down.
At that age rolled the first born ocean around the globe. Clouds
formed, rain descended, and winds swept the earth. There was summer and
winter, and day and night.
The centripetal force of the rings was gradually retarded by the
influence of the moon, and the gravital force was increased until the
rings spread over the earth or approached it. When the innermost ring
gradually descended toward the earth and came in contact with the air
it was checked, and necessarily spread out toward the poles. Gravital
force is strongest in the polar regions. If the rings of Saturn and
Jupiter could increase their motion they would rise to greater heights.
If they could become slower they would sink toward the poles.