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

the left bank of the same river. At its right side are several swamps with good
grass. The soil consists of fine gray and yellowish clay, and is very level, having
formerly been a part of the lake-bed. To the north a ridge of hills extends to the
shore of Nganglaring-tso, and on one of their lowest slopes near the river is the
monastery of Selipuk. The pass Sige-la is pointed out to the N.W. with a road to
Yumba-matsen, three days long, passing Ting-chung-tok, Tok-karmar and Palchen-
tso. Another road to Yumba-matsen crosses the Yülo-la; over Dsoji-la a third road
leads to the same district. A high mountain to the S. 41° W. is called Lavar-gangri,
though by some informants this name is attributed to the whole mountainous region
S.W. and S.S.W. To the S. 48° E. there is said to be a secondary pass, Oyar-la, with
a road to the valley of Pedang-tsangpo taking four days. The pass Gäbyi-la is said
to be situated S. 20° E. with its road to the region of Maryum-la. Straight south
is Sumdang-la, from which a branch of the Sumdang-tsangpo seems to derive its
origin. To the S. 10° E. two passes are said to exist: Jaoshe-la and Ner-la with
a seven days' road to Shamsang. South-westwards is a Changma-yubga-la with a
road joining the one over Surnge-la to Tokchen.
The road to Rartse goes over the plain with abundant tussock grass, and a
soil which becomes very swampy after rain. From this place, Camp 441, the
source of the Sumdang-tsangpo is shown to the S. 21° E., and is said to be three
days distant. From Rartse the plain continues to the foot of the hills, but its southern
part is perfectly arid and consists of fine gravel. On account of its level character
there are no signs of old beach-lines on the plain, but along the foot of the hills
they become so much the sharper marked. First it is a series of flat undulations,
then three greater rounded walls, the one in the middle being 7 m high, and, finally,
another series of smaller undulations rising gradually to a kind of terrace which is at
the same level as the highest beach-lines. The aneroids here gave 4 874 m; though
the height from one reading cannot be reliable, the lake should have been some
126 m higher at an earlier, pluvial period, which agrees with the beach-lines I found
at Lakor-tso, which were 133 m high above that lake.
The first hills are crossed in a little pass called Chase-la, 4 953 m high, and
situated in porphyry rocks. The valley on its southern side is formed by the two
valleys of Kyangyang and Kartsak, from S.W. and S.E. At Kyangyang, Camp 442,
the height is 4 977 m, and the rock porphyry.
The Kyangyang valley rises slowly to the double pass Kyangyang-la with a
height of 5 157 m. To the S. 23° E. is the district Sumdan-changma; S. 10° E. is
Pang-nagrong; S. 5° E. is Molung, a valley with a road to Molung-la and Tokchen,
now reported to be impossible for traffic on account of there being more ice and
snow than usual. This Molung-la must be situated in the same range as the Ding-la;
and as the Ding-la was one of the most difficult passes in the whole system, the
Molung-la is probably very inconvenient, though not belonging to the continental
water-parting. To the S. 1° E. is the valley Gangchen, and S. 42° W. Gangchung;