of miles of lowlands, where
the the 1859 1860 1861 | the 1866 1869 1872 |
Alpine species could not possibly exist, is one of the most striking cases known of the same species living at distant points, without the apparent possibility of their having migrated from one
to to 1859 1860 1861 | point to 1866 1869 1872 |
the other. It is indeed a remarkable fact to see so many
of of 1859 1860 1861 | plants of 1866 1869 1872 |
the same
plants plants 1859 1860 1861 | species 1866 1869 1872 |
living on the snowy regions of the Alps or Pyrenees, and in the extreme northern parts of Europe; but it is far more remarkable, that the plants on the White Mountains, in the United States of America, are all the same with those of Labrador, and nearly all the same, as we hear from Asa Gray, with those on the loftiest mountains of Europe. Even as long ago as 1747, such facts led Gmelin to conclude that the same species must have been independently created at several
distinct points; and we might have remained in this same belief, had not Agassiz and others called vivid attention to the Glacial period, which, as we shall immediately see, affords a simple explanation of these facts. We have evidence of almost every conceivable kind, organic and inorganic,
that that 1859 1860 1861 | that, 1866 1869 1872 |
within a very recent geological period, central Europe and North America suffered under an
Arctic Arctic 1859 1860 1861 | arctic 1866 1869 1872 |
climate. The ruins of a house burnt by fire do not tell their tale more
plainly, plainly, 1859 1860 1861 1866 | plainly 1869 1872 |
than do the mountains of Scotland and Wales, with their scored flanks, polished surfaces, and perched boulders, of the icy streams with which their valleys were lately filled. So greatly has the climate of Europe changed, that in Northern Italy, gigantic moraines, left by old glaciers, are now clothed by the vine and maize. Throughout a large part of the United States, erratic
boulders, boulders, 1859 1860 1861 1866 | boulders 1869 1872 |
and
rocks rocks 1859 1860 1861 1866 | rocks 1869 1872 |
scored
by drifted icebergs and coast-ice, by drifted icebergs and coast-ice, 1859 1860 1861 1866 |
rocks 1869 1872 |
plainly reveal a former cold period. |