On the disruption of the Mongol empire, founded by Genghis, and built on by his successors, the tribes who composed it were dispersed far and wide over Europe and Asia, from the Great Wall of China to the Volga and the Black Sea. Their dynastic divisions were numerous, but the Mongol blood was soon lost in many of these. The Khans were often followed into conquered territories by a small proportion only of their own race, sometimes by a few families, and sometimes by a few individuals only, their armies being mainly composed of alien elements. These handfuls of men soon lost their national characteristics under the influence of a settled life, and contact with races better trained in the arts of peace. The numerical superiority of the people among whom they lived, must necessarily have absorbed them; and it would be hard now to trace the Mongol blood in the descendants of the Tartars of the Crimea, of Kazan, of Nogai, or of Kapchak. The homogeneous race of the Mongols may now be divided into the Kalkas, the Kalmuks, and the Bouriats. The Kalkas, who take their name from a small river rising in the Siolki mountains in Manchuria, are a numerous people, occupying the north of the Great Desert. They may be called the Mongols proper, if any are entitled to that name. The Kalmuks, so nicknamed by the Mahommedan Tartars, inhabit the Russian province of Astrakhan. A remarkable exodus of these people took place in 1770-71, on which occasion half a million of the Kalmuks of the Volga fled from the tyranny of Catherine II., and directed their march eastward by the route by which their ancestors had so often travelled to Europe. During their eight months' pilgrimage they were goaded to despair by hunger, weariness, and savage enemies; and when they at last found shelter in the dominions of the Emperor of China, they had been reduced to half their number. The Emperor Kienloong allotted to them a settlement in the province of Dsungaria, on the north-west of the desert. The Eleuths on the south-east of the desert are also of the race of the Kalmuks. The black Kalmuks are settled near the sources of the river Obi, north of the Altai mountains. The Bouriats in the Siberian province of Trans-baikal, although of true Mongol origin, do not appear to have been much mixed up in the military movements of the other tribes. They were nevertheless a warlike people, were subdued by the family of Genghis in the thirteenth century, and made a respectable stand against the Russians in the seventeenth. There are other tribes of Mongols within the modern limits of China proper, though north of the Great Wall. Some of these till the ground, but they are principally kept up as the reserve army of China.