more arid during the period covered by history, all the difficulties disappear. Under less arid conditions, the Niya River would not only be larger, but one or two small streams, which now wither to nothing in the desert to the east, would join it below the modern oasis. The water would be much more free from salt, for a relatively small portion would flow underground. As aridity increased, outlying settlements would be abandoned in the order of their remoteness, and the vegetation around them would gradually die. When the remoter oases had been deserted, it may have happened that the Niyang of Hwen Tsiang persisted for many centuries on the site of modern Niya. Finally, before the time of Marco Polo, 1295 A. D., it, too, must have decayed and vanished, perhaps because of slowly increasing salinity which gradually ruined the fields, as it is now doing once more after their recovery during a long period of rest. It is, perhaps, not insignificant that in one of the wooden documents found by Stein in the main ruins, " we read that all the ` Shodhagas' and ` Drangadaras,' evidently local officials of the district, are complaining of the want of water."
IIIFカラー高解像度
