Note 19 — STEPPES AND DESERTS.

p. 10.—“As if America had emerged later from the chaotic watery covering.”

An acute enquirer into nature, Benjamin Smith Barton, said long since with great truth, (Fragments of the Natural History of Pennsylvania, P. i. p. 4), “I cannot but deem it a puerile supposition, unsupported by the evidence of nature, that a great part of America has probably later emerged from the bosom of the ocean than the other continents.” The same subject was touched on by myself in a memoir on the primitive nations of America (Neue Berlinische Monatschrift, Bd. xv. 1806, S. 190). “Writers generally and justly praised have repeated but too often that America is in every sense of the word a New Continent. Her luxuriance of vegetation, the abundant waters of her enormous rivers, the unrepose of her powerful volcanoes, all (say they) proclaim that the still trembling earth, from the face of which the waters have not yet dried off, is here nearer to the chaotic primordial state than in the Old Continent. Such ideas appeared to me, long before I commenced my travels, alike unphilosophical and contrary to generally acknowledged physical laws. Fantastic images of terrestrial youth, and unrepose associated on the one hand,—and on the other, those of increasing dryness, and inertia in maturer age,—could only have presented themselves to minds more inclined to draw ingenious or striking contrasts between the two hemispheres, than to strive to comprehend, in one general view, the construction of the entire globe. Are we to regard the south of Italy as more modern than its northern portions, because the former is almost incessantly disquieted by earthquakes and volcanic eruptions? Besides, what small phenomena are the volcanoes and earthquakes of the present day, in comparison with those revolutions of nature which the geologist must suppose to have accompanied, in the chaotic state of the earth, the elevation, solidification, disruptions, and cleavings of the mountain masses? Diversity of causes must produce diversity in the operations of natural forces, in countries remote as well as near. Perhaps the volcanoes of the new continent, (of which I still reckon above 28 in a state of activity), have only continued to burn longer than others, because the lofty mountain ridges, on which they have broken forth in rows or series above long subterranean fissures, are nearer to the sea, and because this proximity seems, with a few exceptions, to affect the energy of the subterranean fires in some way not yet sufficiently explained. Besides, both earthquakes and fire-emitting mountains have periods of activity alternating with periods of repose. At the present moment,” (I wrote thus 42 years ago!) “physical disquiet and political calm reign in the New Continent, while in the Old the desolating strife of nations disturbs the enjoyment of the repose of nature. Perhaps a time is coming when, in this singular contrast between physical and moral forces, the two sides of the Atlantic will change parts. Volcanoes are quiescent for centuries before they burst forth anew; and the idea that in the so-called older countries, a certain peace must prevail in nature, is founded on a mere play of the imagination. There exists no reason for assuming one entire side of our planet to be older or newer than the other. Islands are indeed raised from the bed of the ocean by volcanic action, and gradually heightened by coral animals, as the Azores and many low flat islands of the Pacific; and these may indeed be said to be newer than many Plutonic formations of the European central chain. A small district of the earth, surrounded, like Bohemia and Kashmeer, (and like many of the vallies in the Moon), by annular mountains, may, by partial inundations, be long covered with water; and after the flowing off of this lake or inland sea, the ground on which vegetation begins gradually to establish itself might be said, figuratively, to be of recent origin. Islands have become connected with each other by the elevation of fresh masses of land; and parts of the previously dry land have been submerged by the subsidence of the oscillating ground; but submersions so general as to embrace a hemisphere, can, from hydrostatic laws, only be imagined as extending at the same time over all parts of the earth. The sea cannot permanently overflow the boundless plains of the Orinoco and the Amazons, without also overwhelming the plains adjoining the Baltic. The sequence and identity of the sedimentary strata, and of the organic remains of plants and animals belonging to the ancient world enclosed in those strata, shew that several great depositions have taken place almost simultaneously over the entire globe.” (For the fossil vegetable remains in the coal formation in North America and in Europe, compare Adolph Brongniart, Prodrome d’une Hist. des Végétaux Fossiles, p. 179; and Charles Lyell’s Travels in North America, vol. ii. p. 20).