and other more or less nomadic, more or less Aryan peoples who drifted to and fro in a great arc between the Danube and Central Asia. While sections of the Aryans were moving south and acquiring and developing civilization, these other Aryan peoples were developing mobility and nomadism; they were learning the life of the tent, the wagon, and the herd. They were learning also to use milk as a food basis, and were probably becoming less agricultural, less disposed to take even snatch crops, than they had been. Their development was being aided by a slow change in climate that was replacing the swamps and forests and parklands of South Russia and Central Asia by steppes, by wide grazing lands that is, which favoured a healthy, unsettled life, and necessitated an annual movement between summer and winter pasture. These peoples had only the lowest political forms; they split up, they mingled together; the various races had identical social habits; and so it is that the difficulty, the impossibility of sharp distinctions between them arises. Now the case of the Mongolian races to the north and north-west of the Chinese civilization is very parallel. There can be little doubt that the Hiung-nu, the Huns, and the later people called the Mongols, were all very much the same people, and that the Turks and Tartars presently branched off from this same drifting Mongolian population. Kalmucks and Buriats are later developments of the same strain. Here we shall favour the use of the word "Hun" as a sort of general term for these tribes, just as we have been free and wide in our use of "Scythian" in the West.
The consolidation of China was a very serious matter for these Hunnish peoples. Hitherto their overflow of population had gone adventuring southward into the disorders of divided China as water goes into a sponge. Now they found a wall built against them, a firm government, and disciplined armies cutting them off from the grass plains. And though the wall held them back, it did not hold back the Chinese. They were increasing and multiplying through these centuries of peace, and as they increased and multiplied, they spread steadily with house and plough wherever the soil permitted. They spread westward into Tibet and northward and north-westwardly, perhaps to the edge of the Gobi desert. They spread into the homes and pasturing and