AN EXCURSION UP THE EASTERN WATERWAY OF THE TARIM DELTA. 469
our way by a narrow passage, called Dauleti-boltoso, with a shepherd's hut beside it, into the lake of Dunglik-köl, which, as the name implies, is entirely surrounded by tamarisk-mounds. Both these lakes, Tschong-köl and Dunglik-köl, are marginal lakes, without outflow. Dragging our canoes over a tongue of land, we embarked on the Aghisköl, paddled south-west across it, and then made our way back to Kum-tscheke on foot. The result of this little excursion was to demonstrate the existence of a recently formed hydrographical system east of the Ilek system; that is, another step in the migration of the main mass of the water back to the old depression of the Lop-nor, lying north of the Kara-koschun. In this movement we have a signal exemplification of the power of running water, for these new overflows, which are bit by bit encroaching upon the Desert of Lop, are literally breaking down the dunes which stand in their path, and with irresistible energy are making their way directly in the teeth of the prevailing winds and the advancing sand-dunes. Thus they furnish a fresh proof that the dunes fall passive victims . to the erosive, transporting power of the water. On the whole the kamisch and tamarisks were more abundant in this locality than they had been four years before. My guide, Avullu, who on that occasion also acted as my cicerone, assured me that the channel from the Märdäk-köl began to form the year after my visit, but it was not until that very year (I goo) that it grew to any great size.
Fig. 4II. THE LOW RIGHT BANK OF THE ILEK, JUST OPPOSITE KUMI-TSCHEKE.
The stream which issues from the river to feed these new lakes had the following dimensions: breadth, II.06 m.; mean depth, 1.491; mean velocity, 0.3855 m.; volume, 6.36 cub. m. in the second. Of this volume only a little more than one-half, or 3.444 cub. m., reached, as we have seen, the Sadak-köl; the remainder, 2.9 cub. m., is lost on the way through evaporation and absorption.
IIIFカラー高解像度
