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

At the Chaktak junction the river had 90.5cub.m.; at the Dok-chu junction,
305 km. lower down, only 75cub.m.; though many tributaries are received on the
way. The difference of course depends on the fact that the river was measured at
the latter place 53 days before the measurement at the Chaktak junction; it should
also be remembered that all the northern tributaries from the Transhimalaya are
caught by Raga-tsangpo. From the result we get an absolute proof that the Tsangpo
constantly rises from day to day during April and May, a rise which, of course,
continues the whole summer till the absolute maximum is reached.

A small oscillation of the water level of the Tsangpo could be observed. In
the morning of May 29th it stood 25mm. lower than at 3 P. M. the day before;
at 3 P. M. on 29th it had again risen, and stood 15mm. higher than 24 hours
before. This must chiefly depend upon the local weather, and the different speed
of melting day and night in the nearest tributaries.

From Camp 168 our road follows the northern bank of Chaktak-tsangpo N.W.
and W.N.W-wards below or on the top of its 5m. high terrace. The valley is level
to the eye and the current very slow, having no rapids at all. Once or twice the
river is divided into two or three arms. The valley is broad and open, about 1 km.,
and surrounded by rather low mountains, a series of shoulders, generally with some
living rock visible, green schist, either at the base or as ridges on the crest. The
Chaktak-tsangpo is here enclosed between two ridges with short transverse valleys,
a few of them with brooks.

From the left, or north, we observe the following tributaries: Ahlung-rong,
Chang-lung, Muga with a brook forming a little delta at the junction, and coming
from a considerable mountain group in the background; Pelung-ongma, Pelung-
kongma, and Nimdong. Tögden is a promontory just below Camp 169. From the
right or south enter the tributaries: Kha, Tingring, Kera-lung, and Gulung. There
are some good pasture-grounds in the valley and bushes grow at a few places; at
Nimdong were two tents and flocks of sheep and goats. There is not much gravel,
but a good deal of sand, either forming rudimentary dunes, or terraces with steep
sides, and grass on the top. Kyangs are common. Mani-rigmos, chortens and ruins
are often seen along this road which seems to have been very much frequented; the
walls and towers on some hills are probably remains of fortifications from times of
hostility with Nepel.

A half storm was blowing from the west the whole day, and the air filled
with dust.

From Camp 169, at 4,525m. (14,842 feet), we again leave the Chaktak-
tsangpo, and ride up the Takbur valley to the N.N.W., and then turn N.N.E.
rising considerably. This valley is rich both in grass, bushes, water, and wild ani-
mals, such as kyangs, foxes, lynxes, hares, arctomys, rabbits, partridges, pheasants
and small birds. Great flocks of tame yaks are seen. Near the pass a few snow-
patches may still be seen in shady places.