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

TI-IE PASS DANGBÄ-LA.   257

On the way down to Linga, where the Bup-chu valley is enclosed between fairly high mountains, the river receives many tributaries. Only from interpolation and from native reports do I conclude that the joint river from Shib-la and Chesang-la must join the Bup-chu somewhere below the Sham junction. And still lower down the joint Sangra-palhé and Sele-nang runs out into the Bup-chu. This river is therefore of considerable size, in fact I found later on that it carried the same volume as the Mü-chu itself and the question is whether the Bup-chu, as being much longer, should not be regarded as the principal branch. But as the name Mü-chu is used the whole way down to Raga-tsangpo, the brook from Chang-la-Pod-la must still be regarded as the source.

From the Sham junction and upwards there is said to be a village of ten families called Sechen situated in a tributary valley from the left side. Looking up the valley a great mountain massive called Shakchen is seen; west of it is the valley Rakchung and west of that mount Mugmu and the small valley Sechung. The ridge between Bup-chu and Sham is called Dakchung.

A short distance below the Sham junction the Bup-chu receives a tributary from the left, called Dangbä-chu. Two small valleys entering the widening quite close are called Niri and Kejak. The road goes up the Dangbä-chu to the S.E.; it is surrounded by fairly high mountains; Duyung is a left tributary; at Dochen stone-huts are built. Near the right tributary Chagelung a tight, dark quartzite stands in solid rock. The gravel in the valley is chiefly porphyry, schist and conglomerate. From the right side the two valleys Nalung and Dalung enter, and at the point of their junction are two small villages Lundup and Tamring. Camp I 2 I is at 4 619 m.

A little above this camp the tributaries Tsubelung and Lalung enter from the right; another valley from the same side on the way up is Nevo-goma; from the left enter Nevok, Chialung and Lung, where biotite-granite forms solid rock, higher up Yagbe. The mountains round the valley of Dangbä-chu are rather low, and solid rock is rare; detritus of all sizes fills the bottom and the slopes. The whole bottom is full of ice. The gravel and ice together make this road anything but comfortable.

Finally the road leaves the Dangbä-valley which is seen coming from the south, where it is formed by two smaller valleys, Seuk to the east, and Yak-maru to the west. The name Dangbä-chu, however, remains with the small right tributary which comes down from the pass; Larnang is a right tributary to it. The slope up to the pass is covered with blocks of granite. The pass has a height of 5 25o m and is situated between two peaks; it is rather flat.

Dangbä-la has so far a higher hydrographical rank than Shib-la and Chesangla, as it is a water-parting between the system of the Mü-chu to the north and the Rung-chu to the south; the latter goes direct to the Tsangpo below the junction with the Raga-tsangpo. The upper part of the Rung-chu from the pass to Camp 12 2, Ngartang, at a height of 4 909 m, receives a series of small tributaries from both sides, the names

33-141741 III.