OCR Text |
Show 120 STEPPES AND DESERTS. 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 dis- . quiet 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 t.ime 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 valleys 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 |