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

1

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SANDRER(=, HOLDICtI AND GRENARD.

285

where the yellow glacial streams pour down from the outer Himalayan wall, or the clear flow of currents from the central lakes join the main stream ...> .' Further on

Sir Thomas expresses the same view in the following words: Judging from the great

size of these northern tributaries, and the number of them, there certainly seems good reason for supposing that part of the central lake district lies within the Brahma-

putra basin. There is no other way of accounting for their volume. The southern tributaries from the Himalayan glaciers are comparatively insignificant.» 2 And again: ),From some of the innumerable lakes (the desiccating remains of ancient snow-fields which border it3 on the south) it is probable that those big affluents of the Brahmaputra noted by Nain Sing must take their rise ...v4

Such an opinion as this is by no means surprising and does not even seem too audacious. On the contrary. At the time, 1905, when Sir Thomas Holdich published his book, the opinion he expresses was the most likely to be correct. From the material then existing everybody would have been induced to »capture» some of the central lakes within the drainage area of the northern tributaries of the Tsangpo. And nothing else existed, except d'Anville and the Ta-ch'ing map. On both of them two or three of the northern tributaries are actually drawn as coming from lakes. Sir Thomas, however, does not derive his conclusion from the Chinese maps, but from the size of the tributaries and the clearness of their water, as reported by Nain Sing. We have already seen that Montgomerie concluded from the clearness of the water, that these rivers could not be fed by glaciers. Thus, indeed, it would seem likely, that they had passed through lakes.

On F. GRENARD's map 5 Tchou Nag and Tcharta Tchou come from lakes, which, however, are situated south of the main watershed. This is indeed the case with Chaktak-tsangpo (Tcharta Tchou), although its course, as taken from the Chinese map, is rather fantastic.

In 1905 Graham Sandberg expresses his views as follows:6 »The rivers which debouch into the Tåmchhok from the north are all of such considerable volume that they must have had a lengthy run before reaching the point of junction. Accordingly we ought to set back the northern watershed of the Tåmchhok many miles further north than the actual valley line wherein the channel runs. The incoming northern rivers cut through the low lines of hills bounding this valley on the northern banks: whence, then, do they hail ? One would imagine that, in all probability, the massive mountain range, practically a continuation of Mount Kailas, known to geographers as the Gang-dis-ri range (really Gang Tise Ri) stretching east across Tibet, gave

I Ibidem, p. 38. 3 Ibidem, p. 234.

3 Littledale's route westwards.

4 Ibidem, p. 285.

s Carte de l'Asie Centrale dressée d'après les travaux des explorateurs modernes, les cartes chinoises et les renseignements d'indigènes par F. Grenard, dessinée par J. Hansen. 1899.

6 Tibet and the Tibetans, London 1906, p. 79.