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

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less observed by Hindustani visitors, and from its intricate outline less easily comprehended

and described by them    ->

He then gives an excellent description of the western shore of Rakas-tal and is right in saying the southern shore is so irregular, that it has to be surveyed in detail if an idea of its form is to be gained. He passed the Chabgia Gumba without seeing it. The name of the lake was found to be Cho Lagan, and it is not sacred.

At the shore he found marks of variation in the water-level to the extent of a few feet. The water was quite pure and sweet, so the thick efflorescence of salt he found on lately inundated, swampy ground, was supposed to arise from the soil.

Henry Strachey regarded the eventual connection between the two lakes and the Satlej as an essential object of his journey. Regarding the effluence of Rakastal, he arrived at the following conclusion: I

»There is no visible channel from the lake, and the only effluence is by filtration through the porous soil of the intermediate ground, unless it be at times of extreme flood, when the level of the lake may possibly rise high enough to overflow the margin at this corner. The stream so formed flows westward, through an open valley; below Changchung it receives the Sar-chu, a rivulet from the deep ravine immediately west of Kailas; the united stream then takes the name of Lajandak, which is also an encamping ground on its banks about a day's

journey from Gangri     Moorcroft's statement regarding the Tirthapuri river (12th August),
agrees with this account of mine, though not with his own of the 15th, when he made the Chugarh come from Rakas Tal. Hearsay's map makes the same mistake, and on the 13th tdem, he describes two of the four tributary streams from the Gangri mountains large enough io be bridged with Sangas, though he did not notice them on his way out to Manasarowar, 1st and 2d August. The effluence of Rakas Tal probably contributes less to the Sutlej than others of its numerous sources in the Gangri mountains, or the Indian Himalaya, for the Bhotias say, that the stream at Lajandak, even after it has received the Sar-chu, is very inconsiderable. It is a question that can be decided only by actual measurement perhaps, whether the main source of the Sutlej be not in the Darma-Yankti, for the discharge of the Chûgarh sometimes, though not constantly, exceeds that of the joint Tirthapûri and Misar river, as the Bhotias testify, who are in the habit of fording both streams, close above their confluence at Palkia. The former is liable to great floods in the summer, the discharge of the latter being more equable throughout the year.»

Thus Henry Strachey did not find any direct and superficial effluence from the Rakas-tal. The only effluence was by filtration, although he does not say to what depth this filtration goes. He finds it likely that at times of extreme flood there may occur a superficial overflow as well. Moorcroft's mistake as to which branch comes from the lake will be best understood from Hearsay's map (Pl. III). The Tirtapuri Satlej cannot be said to be equable throughout the year. On the contrary, the fluctuation in the volume of water is enormous. After heavy rains on the southern slopes of the Gangri and surrounding mountains, the northern tributaries grow to furious torrents. Supposing that rains chiefly touch the Himalayan side, the Darmayankti will get the most of it and grow to a river several times as big as the

HENRY STRACHE1".

T I.oc. cit. p. 156.