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『東洋文庫所蔵』貴重書デジタルアーカイブ

hibited in d'Anville's map, and in the still ruder copy of the Lama's original
delineation, published by SOUCIET (Vol. I, Pl. LIII), as intervening between their
last station and the lake.

As I have shown before, such a view as Colebrooke's cannot be correct.
But all he finds deducible as authentic information, is »that the lamas reached the
chain of mountains which forms the south-western boundary of Tibet; and halting at
the foot of the range, learned, from the inquiries which they there made, that the
Ganges takes its rise in the opposite side of that chain of mountains. But the whole
of their sketch of the river's course, from the 36th degree of longitude (from Peking)
where their route terminates, to the 43d, in which they make the two furthest
branches of the Ganges turn due south after a westerly course, and thence return
by an easterly course to the same longitude, with little difference of latitude, must
be deemed vague and imaginary, being at best founded on oral information, and
very imperfect notices, hastily collected in a season of danger and perturbation.»

Colebrooke regards Tieffenthaler's results and maps as not undeserving of
attention. But he points out that Tieffenthaler had not surveyed in person the
course of the Sarayu, although the Father made it rise from the Manasarovar, nor
had he seen the Ganges above Dévaprayága, although he delineates its course to
the Gangotri. Major Rennell believed that Tieffenthaler had himself taken the lati-
tude 33° for Gangotri and accepted it on his map, where he tried to adjust to that
position the supposed course of the Ganges as it came out from the lake Mapama
of the Lamas, »imagined to be the same with the Mánasarávara», and down to the
cataract described by Tieffenthaler at Gangotri. Colebrooke finds it strange that
Rennell could suppose that Tieffenthaler had visited Gangotri in person, as Anquetil
du Perron positively says he did not. In the second edition of his Memoir, 1792,
Rennell had detected the error in Tieffenthaler's report, and therefore distrusted the
rest of his information. Rennell now concluded that Alaknanda was the chief branch
of the Ganges, and had its source in the snowy mountains of Tibet. And as to the
source of this river he regards Kang Hi's Lamas as the most reliable authority in
existence. Their report is defective in geometrical exactness but in plain matter of
fact it is trustworthy. And they had reported that the river issued from the lake
Mapama and went westward. He thinks Tieffenthaler's messenger unintentionally
corroborated this report.

In conformity with this notion, Colebrooke points out that most maps which had
afterwards been published, as for instance ARROWSMITH's map of Asia in 1801, and
of India in 1804, represented the Ganges within the chain of snowy mountains
flowing for hundreds of miles from lake Mapama to Gangotri. And both Colonel
Colebrooke and H. T. Colebrooke suspected that this notion, founded on the Lamas'
exploration, rested on very slender and unreliable information. They found it extra-
ordinary that Desideri and Freyre, who stayed nearly two months in Ladak, should
not even mention such a remarkable circumstance as the Ganges flowing past the