The Steppes of Tartary and Mongolia, interrupted, says Humboldt,[33] by chains of mountains of various aspects, separate the ruder peoples of Northern Asia from the primitive races, which have been for ages civilized, of Hindostan and Thibet. Their existence has influenced the destinies of mankind in various important ways. They have rolled back the populations towards the south, and more than the Himálaya, more than the snow-crowned peaks of Serinagur and Goorkha, have raised an obstacle to the alliances of peoples, while opposing, in the north of Asia, insuperable barriers to the refinement of manners and the genius of the arts. But it is not only as barriers that History should regard the plains of Central Asia; they have several times let loose on earth a torrent of calamity and devastation. The pastoral races of the Steppes--Mongols, Getæ, Alans, and Huns--have convulsed the world. If, in the course of ages, intellectual culture has directed its course from east to west, like the vivifying light of the sun, Barbarism at a later period has followed in the same track, when threatening to plunge all Europe into darkness. A people of tawny shepherds, Tou-Kin (that is to say, Turkish) in origin, the Hioung-Nou, inhabited, under tents of skin, the elevated Steppe of the Gobi. Long formidable to the Chinese power, a horde of the Hioung-Nou was driven back towards the south into Central Asia. The impulse which they gave spread uninterruptedly even into the native country of the Fins, on the borders of the Oural, and thence the Huns, the Avars, the Chasurs, and various mixtures of Asiatic races, poured forth in furious violence. The Hunnish hosts first appeared on the banks of the Volga, then in Pannonia, and finally on the banks of the Marne, and on those of the Po, ravaging the beautiful fields where, from the days of Antenor, the genius of man had accumulated its glorious monuments. Thus from the Mongolian deserts blew a pestiferous wind, which choked even in the Cisalpine plains the delicate blossom of art, the object of such tender and continual cares. Our English traveller, Atkinson, has called the Steppes "the cradle of invasions;" and this not only because from their solitudes issued the hordes which devastated Europe in the first centuries of the Middle Ages, but because Russia and Austria have found therein those truculent soldiers of repulsive aspect who, in their hands, have become, even in our own day, the scourge of the free and civilized nations they would fain have subjugated.