villages in this part of the country are as changeable as the river-bed itself. The village just named was abandoned in consequence of its being threatened by inundation, and because it was cut off from the country behind by temporary marshes and lakes. When this happens, the inhabitants prefer to flit their Penates to a place of greater safety; and though they carry away all their movable property with them, such as their implements, instruments, fishing-nets, and so forth, they leave their huts behind, partly because the materials of which they are built are valueless, consisting as they do of nothing but poles, branches of trees, and reeds, and partly because they imagine it would be convenient to have the old huts to return to in case the river should once more shift its channel.
The river-bed bears in this locality the most unmistakable evidences of being a quite recent creation. It is practically an overflow current which is actively engaged in excavating its own channel by erosion. Sedimentary deposits, with young reeds just springing up on them, stretch in every direction. The velocity of the current is as much as 1.2 to 1.4 m. in the second; and as one watches it one can see how it successfully accomplishes its purpose step by step. Under the convex banks, where the current is slowest, the sedimentary matter is being deposited in crescentic belts. On the other hand the concave parts of the opposite banks are being subjected to a vigorous assault. These processes are illustrated in the accompanying fig. 15o. The final result is the well scarped and distinct river-bed with which we have become so familiar. The irregularities which show themselves in the development of the river-bed, whereby some windings become much deeper and longer than others, are in this flat and uniform region due to positively trivial causes, such as tamarisks binding the ground together with their roots, the presence of a reed-bed, and so forth. For some distance there lies here, north of the existing river, an arm which was deserted only a year ago.
Fig. I so.
The main river now crosses what six years ago was the lake of Lolo Kullunuuktasi, but is now completely filled up by its sediment; and the village of Tschulum Kulluden-ot-kätkän, on its left bank, has been deserted for the same reason as the village I last mentioned. Here there are both living and dead poplars standing in the middle of the river, a sure indication of the country having been quite recently put under water. On the right bank lies the lake of Uktasi, with the homestead of Uktudeki-uj; the former is fed by a canal (atscha) from the river. A portion of its water returns to the river at Scharkurun (Cataract Arm), while another portion (about which I have more to say later on) makes its way into the old bed of the Tarim and the Katik-arik. South of Uktasi lies amongst the sand the lake of Talaschti, equalling in area the Ullugh-köl.
IIIFカラー高解像度
