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

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ers the Soma-tsangpo. Gyamtse and Migot are mountains at the northern shore. At
Camp 412, Tertsi, a fresh-water spring comes up; a little further west opens the
valley Tsalung, and beyond it is mount Tsabuk. Laronong-chung is a red mountain
to the W.N.W., also belonging to the southern range.

The road to Mendong proceeds W.N.W. over the extensive plain, which is
the western continuation of the bottom of Teri-nam-tso. The ground is perfectly
level to the eye. The road goes near the foot of the southern mountains; from
a southern valley a bed issues between erosive terraces 3 m high. There are
many such valleys from both sides. At the foot of a red rock of quartz-porphyry,
swampy ground surrounds some fresh-water pools called Longgyo-tso. Along the
foot of the southern hills, old beach-lines are sharply developed. The ground is arid,
consisting of clay and fine gravel, seldom interrupted by belts of meagre grass; a
curious depression of almost white clay is passed. The monastery Mendong-gompa
is situated on the left bank of the Soma-tsangpo at the foot of its erosion terrace
which here is some 10 m high; the right side terrace is in two stories. The river
carried (May 26th) about 11 cub. m a second. During the rainy season it cannot
be crossed, especially as its bottom is quicksand. The river, which is one of the largest
of the Tibetan plateau land, is here also known under the name of Nyagga-tsangpo.

The following information was given at Mendong. Tachung is a mountain to
the south, and Tachen to the S.S.W.; S. 31° W. the Soma-tsangpo issues from its
mountain valley; Rabalu is a dominating mountain S. 50° W.; S. 62° W. is the
valley Tsong-kende; Nara is a mountain to the N. 89° W.; Nevem is a low threshold
in the latitudinal valley in which the so called serpun-lam or gold-inspectors' road
passes; further west there is said to be a higher pass, Gaktsang-la, crossed by the same
road; to the N. 59° W. is visible the top of a mountain, near which the Pelung-la is
situated; east of it are two other passes, Tarchok-la and Chöne-la; all these are
said to belong to the range which, to the north, bounds the latitudinal valley
of Teri-nam-tso; this range runs south of and parallel to the greater range, the
highest peak of which is Shakangsham; north of Mendong-gompa there is said to be a
latitudinal valley between these two ranges, including a lake, Dashung-tso, situated
N. 46° W. from Mendong, and not larger than the Chunit-tso; it does not receive
any rivers, only temporary watercourses after rain; other lakes are not to be found
in the surroundings of Mendong. Yage-tarna is a mountain N. 25° W., and east of
it is the valley Yage-lungpa; to the north is mount Mage; N. 12° E. is a valley
Yüchen, through which a road goes to the upper Bogtsang-tsangpo; N. 39° E. is a
group of red mountains, Togmar, and farther east are two low mountains, Topchen-
nakta; E.N.E. are the valleys Gangni, Dorta and Tsüngen; still farther east the
northern mountains disappear in the haze of the far distance; only Targo-gangri
rises above everything else and is said to be seven days distant.

Mendong-gompa is at a height of 4 693 m, only a few metres above the lake.
Camp 414, Sok-yung is at 4 714 m. Thus the rise is gradual and the Soma-tsangpo