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

wide and navigable. In the same way the waters descending from Ngari Giongar on the east-
ern side flow first into the said lake Retoâ, then, following their way down, they form the river
Ganges. A proof of that is to be found in the following fact. The golden sand of the Ganges
is greatly renowned in the writings of our ancestors; therefore, if we would assume that the
origin and source of that river were in a different place, we should stain our ancestors as liars,
because in no other place of the river course (except in Mount Ngari Giongar and in lake
Retoâ), even the slightest appearance of such sands is to be found. On the contrary, if what
I just have said be accepted, that is to say that the source of the Ganges is situated on the
said mount and summit of Ngari Giongar and in lake Retoâ, the statement of the ancient writers
will be found to be really in accordance with my opinion, because, as it is well known, I dare
say, throughout the world, on the shores and in the sands of that lake much loose gold is to
be found, which from the surface of Mount Ngari Giongar and other intermediate mountains,
is carried down by the waters flowing from thence. To search for such gold and to collect
it, Tibetans and some merchants meet from time to time at the said lake, and draw much
profit from it. Moreover that lake is the object of a great veneration by those superstitious
people; therefore they meet sometimes there in a pilgrimage, and make the tour all round
the lake with great devotion believing to acquire many indulgences, and in some way to win
many particular jubilees.»

The lake of Retoâ is of course the Manasarovar. It cannot possibly be any other
lake. Retoâ or Redoc is Rudok, a name which he has heard and either misunder-
stood or misplaced when writing his narrative. He has heard that the Ganges was
supposed to originate from the lake, exactly as the Lama surveyors were informed
and as they represented it on their map. And they visited the lake at the same
time as Desideri. But Desideri is more critical than the Lamas on this particular
point, because he has observed personally and heard from others, that both the
Indus and the Ganges have their sources on Mount Kailas. Regarding the Indus
he has not the slightest doubt of this being the case, »as is practically shown by
facts». But as to the Ganges, he agrees that from its source in the Kailas it really
runs through the lake. And later on he reiterates that the source of the Ganges
is situated on the summit of the Kailas and in the lake. Thus he criticises the
general supposition of his time only so far that he says the lake is only a secondary
source of the Ganges, Mount Kailas being the real and primary source. He de-
scribes the course of the Indus all the way down. It is a pity that he does not say
where his Ganges goes to. For there can be no doubt that it is the same as the
Ganges of the Lamas, i. e. the Satlej.

Desideri confirms the hydrography of the Lamas indirectly. »Parmi però,
da quel che ho nel passaggio osservato . . .!» He refers to his own observations on
his way. He has seen that the source of the Ganges is situated on the Kailas, by
which he means one of the small rivers going down to the Manasarovar. And, if he
has made the wandering round the lake, he has seen the branch, Ganga, going out
of the lake, and therefore gives two sources: Kailas and Manasarovar. He is not
to be blamed in placing the source of the Indus on the western side of the Kailas.
This has been done 190 years later. He does not know Langak-tso at all.