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

is a very flat and broad part of the valley of Angsi-chu which is a tributary
to the Chema-yundung, from the left, or west. To the N.W. is a mountain Lapsi-
ngava beyond which Gunchu-tso is situated.¹ To the N.N.W. are pointed out a
region Nagra, a plain Ronggak-kyermok, and a lake Kuru-chok. N. 13° W. is a
hill Seu-tokar, N. 37° E. the Transhimalayan valley Sabsang, said to contain the
main branch of the Maryum-chu. A valley to the N.E. was called Talung-kongyok.
To the N. 64 E. is a plain called Charko, below the ridge of Tugri-la. N. 70° E.
a part of the broad and open valley of the Chema-yundung can be seen.
The valley going down from the pass is called Tugri-kunglung; the living
rock at its sides is serpentine of pyroxenite and diabas. The valley is rich in grass,
and continues N.N.E. to Chema-yundung. Leaving it to our right we ascend the little
pass Seu-kamba-la, 5,056 m. (16,584 feet) high, on the western side of which the valley
Seu-kamba-lungpa is directed to the north. Following it down we soon enter the
valley of Chema-yundung which here is broad and flat as a plain; the river itself was
spread over a bed more than 150 m. broad, but the depth was only 0.12 m. on an
average, and the current amongst the gravel very slow. The greatest part of this
water seems to come down from a considerable glacier situated amongst the gangris
of Chema-yundung-pu. Seven black tents were pitched near the river. The region
is called Buk-gyäyorap and the height is 4,870 m. (15,974 feet). Even here, at per-
haps 12 or 15 miles from its source, the Chema-yundung flowed at a greater height
than the very source of the Kubi-tsangpo, 4,864 m. (15,954 feet). Unless the current
of the uppermost Chema-yundung is as slow as that of the Kubi, the source of the
western river must be at a considerably greater elevation than that of the eastern.
The Chema-yundung seems to be a few miles longer than the Kubi. So in length
and absolute height the western branch is no doubt more distinguished than the
eastern. But the volume of water is overwhelming in the latter, and all who in
future see both rivers will agree with the Chinese and Tibetans, as I did, and call
the Kubi-tsangpo the source of the Brahmaputra. On account of its great volume
of water, provided from four great glaciers and several small ones, the Kubi has had
force and energy enough to work down its valley deeper than the Chema-yundung,
and this may be one of the causes of the difference in absolute altitude.
The most comfortable and shortest way to Tag-la or Tamlung-la would have
been to follow the course of the Chema-yundung and its tributary Angsi-chu to the
west, which would have spared us the Marnyak-la; but I had to take the longer and
more difficult way to the north to reach a Camp where new guides and yaks
could be had, as my men from Shamsang had to return from here. However, I could
see from my road that it was easy to pass from the uppermost Brahmaputra to the
uppermost Satlej without crossing any other pass than the flat and comfortable Tag-
or Tamlung-la.