Not a member?     Existing members login below:

Young Folks' Library: Wonders of Earth, Sea and Sky

America The Old World
(From Geological Sketches.)
By
L. AGASSIZ.
First-born among the Continents, though so much later in culture and civilization than
some of more recent birth, America, so far as her physical history is concerned, has been
falsely denominated the New World. Hers was the first dry land lifted out of the waters,
hers the first shore washed by the ocean that enveloped all the earth beside; and while
Europe was represented only by islands rising here and there above the sea, America
already stretched an unbroken line of land from Nova Scotia to the Far West.
hypothetical. Yet the progress of science is so
rapidly reconstructing the past that we may hope to solve even this problem; and to one
who looks upon man's appearance upon the earth as the crowning work in a succession of
creative acts, all of which have had relation to his coming in the end, it will not seem
strange that he should at last be allowed to understand a history which was but the
introduction to his own existence. It is my belief that not only the future, but the past also,
is the inheritance of man, and that we shall yet conquer our lost birthright.
materials; because the
agencies that were at work then are at work now, and the present is the logical sequence
of the past. From artesian wells, from mines, from geysers, from hot springs, a mass of
facts has been collected, proving incontestably the heated condition of all substances at a
certain depth below the earth's surface; and if we need more positive evidence, we have it
in the fiery eruptions that even now bear fearful testimony to the molten ocean seething
within the globe and forcing its way but from time to time. The modern progress of
Geology has led us by successive and perfectly connected steps back to a time when what
is now only an occasional and rare phenomenon was the normal condition of our earth;
when the internal fires were enclosed by an envelope so thin that it opposed but little
resistance to their frequent outbreak, and they constantly forced themselves through this
crust, pouring out melted materials that subsequently cooled and consolidated on its
surface. So constant were these eruptions, and so slight was the resistance they
encountered, that some portions of the earlier rock-deposits are perforated with numerous
chimneys, narrow tunnels as it were, bored by the liquid masses that poured [pg 48] out through
them and greatly modified their first condition.
47]
In the present state of our knowledge, our conclusions respecting the beginning of the
earth's history, the way in which it took form and shape as a distinct, separate planet,
must, of course, be very vague and [pg
46]
Even now our knowledge carries us far enough to warrant the assertion that there was a
time when our earth was in a state of igneous fusion, when no ocean bathed it and no
atmosphere surrounded it, when no wind blew over it and no rain fell upon it, but an
intense heat held all its materials in solution. In those days the rocks which are now the
very bones and sinews of our mother Earth—her granites, her porphyries, her basalts, her
syenites—were melted into a liquid mass. As I am writing for the unscientific reader,
who may not be familiar with the facts through which these inferences have been
reached, I will answer here a question which, were we talking together, he might
naturally ask in a somewhat sceptical tone. How do you know that this state of things
ever existed, and, supposing that the solid materials of which our earth consists were ever
in a liquid condition, what right have you to infer that this condition was caused by the
action of heat upon them? I answer, Because it is acting upon them still; because the earth
we tread is but a thin crust floating on a liquid sea of molten [pg
 
Remove