plants; while many are radiant with the effulgence of lichen-like tufts of salt, scattered irregularly over the clayey soil like newly fallen snow. These Mongolian and Tartar Steppes, which are intersected by numerous mountain chains, separate the ancient and long-civilized races of Thibet and Hindostan from the rude nations of Northern Asia. They have also exerted a manifold influence on the changing destinies of mankind. They have inclined the current of population southward, impeded the intercourse of nations more than the Himalayas, or the Snowy Mountains of Sirinagur and Gorka, and placed permanent limits to the progress of civilization and refinement in a northerly direction. History cannot, however, regard the plains of Central Asia under the character of obstructive barriers alone. They have frequently proved the means of spreading misery and devastation over the face of the earth. Some of the pastoral tribes inhabiting this Steppe,—the Mongols, Getæ, Alani, and Usüni,—have convulsed the world. If in the course of earlier ages, the dawn of civilization spread like the vivifying light of the sun from east to west; so in subsequent ages and from the same quarter, have barbarism and rudeness threatened to overcloud Europe. A tawny tribe of herdsmen[11] of Tukiuish _i. e._, Turkish origin, the Hiongnu, dwelt in tents of skins on the elevated Steppe of Gobi. A portion of this race had been driven southward towards the interior of Asia, after continuing for a long time formidable to the Chinese power. This shock, (dislodgement of the tribes) was communicated uninterruptedly as far as the ancient land of the Fins, near the sources of the Ural.[D] From thence poured forth bands of Huns, Avars, Chasars, and a numerous admixture of Asiatic races. Warlike bodies of Huns first appeared on the Volga, next in Pannonia, then on the Marne and the banks of the Po, laying waste those richly cultivated tracts, where, since the age of Antenor, man’s creative art had piled monument on monument. Thus swept a pestilential breath from the Mongolian deserts over the fair Cisalpine soil, stifling the tender, long-cherished blossoms of art! From the Salt-steppes of Asia,—from the European Heaths,—smiling in summer with their scarlet, honey-yielding flowers,—and from the barren deserts of Africa, we return to the plains of South America, the picture of which I have already begun to sketch in rude outline. But the interest yielded by the contemplation of such a picture must arise from a pure love of nature. No Oasis here reminds the traveller of former inhabitants, no hewn stone[12], no fruit-tree once cultivated and now growing wild, bears witness to the industry of past races. As if a stranger to the destinies of mankind, and bound to the present alone, this region of the earth presents a wild domain to the free manifestation of animal and vegetable life.