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

ch'ing and on d'Anvilles map the two Chinese itineraries are laid in. The northern
itinerary does not at any point, west of Lhatse-dsong, cross the Tsangpo. But it
crosses the Maryum-chu and its tributary Tchar tchou before it reaches Gunchu-tso.
Thus it follows a road which runs south of the ordinary road over Maryum-la. It
must be the same road which was followed by Kawaguchi. For he came from
Gunchu-tso and kept south of Maryum-la and »went on several low undulating hills,
and finally reached the lower course of the river Chema Yungdung», after which he
crossed the »Kobei-chu». Thus he left the Chinese itinerary on his left and had not
to cross the Maryum-chu. The Chinese itinerary crossed the Maryum-chu, Kawaguchi
the Kubi-tsangpo. But on the road to Gunchu-tso both must have crossed the same
river. And as this is called Chema Yungdung by the Japanese, it must be the same
in the Chinese case, which also corresponds perfectly with real facts, so much the
more as there is no other sign of a junction between the Chema-yundung and
Maryum-chu on the map.

The first-mentioned of the two principal rivers, the Tamchok-kamba, has its
sources in the mountains of Kouben gang tsian, Goumang and Tam tchouk khabab.
The first of these is Kubi-gangri, which is very well placed on the Ta-ch'ing map.
The second, Goumang, corresponds exactly to Chema-yundung-pu, i. e. the mountain
massive from which the Chema-yundung comes down, and which is probably some-
times called Chema-yundung-gangri, although I only heard it called »pu» or »upper
valley». From the eastern slope of the mountain a river goes down to a little lake,
on the Ta-ch'ing map called L. Djima Young rong, which also proves that Mt.
Goumang must be identical with the Chema-yundung-pu. The third mountain, Tam
tchouk khabab, has, curiously enough, been placed north of Mt. Goumang and a
little tributary, possibly the Angsi-chu, may be said to rise from its eastern slopes.
Thus Langchen-kabab and Tamchok-kabab become, on this map, very close neigh-
bours, and the source of the Horse is regarded as situated at the head of the river
which is farthest west, and, probably, somewhat longer than the other branches. In
this particular detail the different Chinese versions do not agree. For in the version
translated by Klaproth it is said that the Tsangpo comes from Tamchok-kabab and
after a course of 10 lieues receives a tributary from the lake Chema-yundung. Here
it is specially pointed out that only the head river comes from Tamchok-kabab.
With this d'Anville's map agrees for it places Tamchok-kabab as belonging to or
being a part of Kubi-gangri, and Dutreuil de Rhins says of the Tamchok-kamba
that it is »la branche principale du Tsan po».¹

The mistake of the Ta-ch'ing map has of course been accepted by d'Anville,
for in the general hydrographical arrangement both maps are practically like each
other. It is very easy to find out how this mistake could rise, if we only consider
the itineraries on the Ta-ch'ing map. The southern itinerary has crossed the Kubi-