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

South of it is Haraousso, a river flowing eastwards, which comes to an end
before reaching the eastern boundary of Tibet. Compared with the situation of
Poutala and Retink this river ought to be the Tsangpo, but unfortunately Dame, a
place in later years mentioned by della Penna and Nain Sing, is south of it,
and, still worse, so is Lassa or Barantola the capital of Boutan. The Haraousso is
therefore simply Nak-chu, or the upper Salwen, in the neighbourhood of which I was
stopped by the governor of Nak-chu in 1901.¹ Nak-chu means Black water, and so
does Hara-ussu in Mongol. A good number of Mongol nomads are living in this
region.² This explains why the Mongol and not the Tibetan name has reached
Delisle.

As could be expected Grueber's route from Lassa to Agra is entered. Be-
tween Lassa and Tache Linbou (Tashi-lunpo) it crosses a range of mountains, the
later on so famous Kamba-la, which is not mentioned in Grueber's narrative. Then
follow M. Langur or Himalaya, which is correctly shown as a continuation of M. de
Naugracut, and, on the southern side, Couti, Nesti, Catmendour-Patan, Necbal, Etonde,
Patna and Benares. At some distance from Tache Linbou is a mountain Zeketcha,
which seems to be identical with Shigatse. Grueber had forgotten the magnificent
river he crossed south of Lassa, and therefore no sign of the Tsangpo is here to be
seen on Delisle's map.

It is surprising that the Tsangpo-Brahmaputra could keep itself hidden for such
a long time. The Indus and Ganges have been known ever since Alexander's days,
and even the Satlej is marked on Ptolemy's map. In 1705 Delisle believes that he
has placed the sources of these three rivers fairly correctly. But he does not so
much as suspect the existence of the Tsangpo. Through thousands of years this
river remains concealed between Himalaya and Transhimalaya. And still it had been
crossed by Odoric, Grueber and Dorville, and perhaps Verbiest and Gerbillon and
other Jesuits in Peking had heard it mentioned, for to the Chinese it was very well
known. When the members of the French Academy of Science, together with the
learned Jesuits in Peking, so late as in 1705, — and after having gathered informa-
tion about Hatun-ussu, Mur-ussu, Akdam, and Nak-chu, had not succeeded in finding
the least sign of the Tsangpo, one may be justified to ask how ever it would have
been possible for Ptolemy to draw a map of the whole course of the Tsangpo!

That the transverse valley of the river through Himalaya was unknown to
Delisle is not surprising, for it cannot be said to be more than superficially known
even in our days. But the lowest part of the river appears now for the first time,
under the name of Laquia, perhaps on account of its coming from the district of
Lakhimpur? It takes its origin in the Lac de Chaamay, which now, as a rather
suspicious object, has been deported into the unknown darkness of Indo-China.