All the continents which now exist were, it is well understood, once,
under water, and the rocks of which they are composed were deposited
beneath the water; more than this, most of the rocks so deposited were
the detritus or washings of other continents, which then stood where the
oceans now roll, and whose mountains and plains were ground down by the
action of volcanoes and earthquakes, and frost, ice, wind, and rain, and
washed into the sea, to form the rocks upon which the nations now dwell;
so that we have changed the conditions of land and water: that which is
now continent was once sea, and that which is now sea was formerly
continent. There can be no question that the Australian Archipelago is
simply the mountain-tops of a drowned continent, which once reached from
India to South America. Science has gone so far as to even give it a
name; it is called "Lemuria," and here, it is claimed, the human race
originated. An examination of the geological formation of our Atlantic
States proves beyond a doubt, from the manner in which the sedimentary
rocks, the sand, gravel, and mud--aggregating a thickness of 45,000
feet--are deposited, that they came from the north and east. "They
represent the detritus of pre-existing lands, the washings of rain,
rivers, coast-currents, and other agencies of erosion; and since the
areas supplying the waste could scarcely have been of less extent than
the new strata it formed, it is reasonably inferred that land masses of
continental magnitude must have occupied the region now covered by the
North Atlantic before America began to be, and onward at least through
the palaeozoic ages of American history. The proof of this fact is that
the great strata of rocks are thicker the nearer we approach their
source in the east: the maximum thickness of the palaeozoic rocks of the
Appalachian formation is 25,000 to 35,000 feet in Pennsylvania and
Virginia, while their minimum thickness in Illinois and Missouri is from
3000 to 4000 feet; the rougher and grosser-textured rocks predominate in
the east, while the farther west we go the finer the deposits were of