国立情報学研究所 - ディジタル・シルクロード・プロジェクト
『東洋文庫所蔵』貴重書デジタルアーカイブ

BROOKS AT THE NORTHERN SIDE OF GURI,A-MANDATA.

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The two largest valleys ' situated on the northern side of Gurla are called Namreldi I and Sälung-urdu. Riding up from Camp 218 to the first-mentioned, one has to cross some narrow belts of vegetation, and then the flat grey scree of gravel from Sälung-urdu furrowed by now dry water-courses diverging towards the lake. They prove that sometimes such powerful floods may come down from the mountain, that they keep on the surface almost the whole way clown. A road from Tugu-gompa to Taklakar in Purang crosses the fan. Where this fan and that from Namreldi come in contact with each other, a low wall of gravel is formed.

Reaching the foot of the mountain one has to cross a rock spur on the eastern side of which one comes down into the Namreldi valley, a little above the point where it leaves the mountain and opens out to the fall with its regular slope down to the southern shore of the MMIanasarovar. The passage through which it goes out is as narrow as a gate, almost filled with the water of the river. So far as one can see, the valley is very narrow and wild; the snow-slopes of Gurla, which are so splendidly visible from the lake, are now hidden by the nearest parts of the mountain.

At noon, on August 12th, the brook had here a breadth of 9.43 m., an average depth of 0.28 m., an average velocity of 1.16 m., and a volume of 2.86 cub. nl. Of this volume, as was found the day before, only 1.07 cub. m. reaches the lake on the surface of the earth, though the two measurements cannot be compared, as the Namreldi rises considerably towards evening. Its water is perfectly clear which seems to indicate that it does not come direct from a glacier. At this place and on the little spur west of it the rock is white and grey granite and gneiss-granite, dipping 29° N. 33° E.

For a distance of a few kilometers along the northern foot of Gurla, from Namreldi to Sälung-urdu, there is nothing but blocks, gravel and sand, sometimes covered with scanty vegetation. Everything is granite and gneiss. The Sälung-urdu comes from a glacier visible from the lake. The water is full of glacial clay. The breadth of this brook was 5 m., average depth 0.28 m., average velocity 1.29 m., and volume 1.81 cub. m. No superficial water reaches the lake. The brook had a temperature of 3.2° C., almost the same as in the springs near Camp 218. Looking northward to the lake one sees that the fans from these two valleys form convexities in the shore-line, and probably the varying depths in the southern part of the lake depend on the continuation and situation of these fans.

Following the shore northwards from Camp 2 I 8, we find the same long narrow lagoons as before separated from the lake by a low mud wall. The open space between the hills and the lagoons is very narrow. Inside of the lagoons is a bed of dead alga, then follows coarse sand and gravel rounded by the waves; on the slope of the hills there is a terrace some 4 m. high and above it some vegetation of small bushes. The lake is shallow at 50 to 8o M. from the shore and is here very muddy; one sinks to the knees if walking near the lagoons.

I Some Tibetans called it Namreling.