much progress in breaking up the continuity of the loess steppes, and to widen the distânce between habitable areas within the region thus isolated. The reaction did not begin until the inflow of water became insufficient to maintain the inland sea at its maximum of expansion. After this would come the change to segregation of communities, first into larger groups of loosely connected units, then the breaking up of these into smaller groups. Within the wider limits of the region more or less intercourse could exist between the delta-oases on some stretches along the piedmont belt, and often still more easily between those on opposite sides of relatively low mountain ranges. The essential condition was a sufficient frequency of springs or streams to permit travel on foot.
Under such conditions, continued through thousands of years, the related peoples, becoming isolated in oases or oasis groups, or in high mountain valleys, would differentiate, each evolving its own culture along lines influenced by inherited traditions, environment, and racial character. The development would, in general, on account of isolation, be peaceful, and, while alone and uninterrupted, would lack the benefit of acquisition of the new factors that come with intercourse with unrelated peoples. The growth of population on these restricted areas was necessarily accompanied by evolution in social organization. We find the people living in towns, where the long continuance of life under individual town government, practically without external relations, while developing individuality, must have given the many separate peoples thus situated certain fundamental political characteristics common to all. In the same way, in so far as the physical environment was similar, certain classes of customs, arts, and occupations must have evolved along similar lines. In so far as the peoples of larger or minor groups of oases differentiated from the same stock or from the same language stock, their languages would retain traces of the original generalized speech. All these are ethnographic data to be carefully searched for in sifting and analyzing the results of future investigations.
But several data among our finds from this earliest Anau culture show that more or less intercourse existed with other parts of the oasis-world. Turquoise beads, used as burial gifts with the skeleton of a child, must have come from Persia, where turquoise is known both to the south of Anau and farther eastward on the plateau; the same inference is to be drawn from the presence of copper.
We have at present no means of knowing how the earliest culture of the settlements at Anau stands in relation to the generalized cultures of Central Asia before the segregation into isolated communities, for there have been made no other systematic excavations anywhere to discover traces of the older civilizations, excepting in Susiana, southwest of the Iranian plateau, to which I shall refer farther on. The constituents of the earliest culture found at Anau presuppose a previous evolution during many thousand years. How slow it must have been is shown by the almost unvarying character of the pottery during the two millenniums at the North Kurgan.
When we compare this culture with that which succeeded it (No. II) on the same kurgan, we find both differences and points in common. Each has its own peculiar technique in pottery and scheme of ornamentation in painted decoration. The mace and artificially formed slingstones appear. But both cultures had in
IIIF Color HighRes
