hunting-grounds of the Hunnish nomads, exactly as the white people of the United States spread westward into the hunting-grounds of the Red Indians. And in spite of raid and massacre they were just as invincible because they had the pressure of numbers and a strong avenging government behind them. Even without the latter support the cultivating civilization of China has enormous powers of permeation and extension. It has spread slowly and continuously for three thousand years. It is spreading in Manchuria and Siberia to-day. It roots deeply where it spreads.
Partly the Huns were civilized and assimilated by the Chinese. The more northerly Huns were checked and their super-abundant energies were turned westward. The southern Huns were merged into the imperial population.
If the reader will examine the map of Central Asia, he will see that very great mountain barriers separate the Southern, Western, and Eastern peoples of Asia. (But he should be wary of forming his ideas from a map upon Mercator's projection, which enormously exaggerates the areas and distances of Northern Asia and Siberia.) He will find that from the central mountain masses three great mountain systems radiate eastward; the Himalayas going south-eastward, south of Tibet, the Kuen Lun eastward, north of Tibet, and the Thien Shan north-eastward to join the Altai mountains. Further to the north is the great plain, still steadily thawing and drying. Between the Thien Shan and the Kuen Lun is an area, the Tarim Basin (= roughly Eastern Turkestan), of rivers that never reach the sea, but end in swamps and intermittent lakes. This basin was much more fertile in the past than it is now. The mountain barrier to the west of this Tarim Basin is high, but not forbidding; there are many practicable routes downward into Western Turkestan, and it is possible to travel either along the northern foothills of the Kuen Lun or by the Tarim valley westward from China to Kashgar (where the roads converge), and so over the mountains to Kokand, Samarkand, and Bokhara. Here then is the natural meeting-place in history of Aryan and Mongolian. Here or round by the sea.
We have already noted how Alexander the Great came to one
