tion of the fresh water by subterranean means that the sp. gr. of the water in the south of the Selling-tso was not higher than i .0245.
From the fourth beach-terrace upwards, the slope was scored with a small freshwater rivulet, then however dry. This derives its water chiefly from rain; but it is also possible, that in its upper part springs gush out at the season when the Naktsong-tso is receiving its supplies from the south, and that this is consequently one of the points where the otherwise subterranean surplus water makes its appearance at the surface. To the eye the ground below the lowest (sixth) terrace is perfectly level, and consists of fine mud, which, next the water's edge, was so saturated with moisture, and so soft, that we had great difficulty in getting our skiff launched. We then found ourselves in a bay, inclosed between excessively level sedimentary deposits, low and barren, and lying almost flush with the water, these being the parts of the lake-bottom which were the last to be exposed. The bay is shallow: the soundings taken in it were as follows = 0.9, 2.25, 2.67, and 2.04 m., this last being taken at its entrance, where the bay contracts somewhat. From that spot I noted the extreme northerly cape of the southern shore bearing N. 67° E.; it was in that direction that the lake appeared to extend farthest, indeed it attains quite noteworthy dimensions. The mountainous country on the east was hardly distinguishable, appearing only as a faint yellowish red mist. But the little steep range on the blunted peninsula of the northern shore, with its loaf-shaped rocky summits, was nearer and distinctly visible, as also were the mountains south of the lagju-rapga, which lie along precisely the same line as the range last mentioned.
The lake-bottom consists of grey-blue clay; and the water had a light-green tint, being very muddy in the bay, but clearer outside. Nevertheless we were unable to see the bottom, partly because of its confusing colour and also because of the absence of Alga or other objects to break the uniformity. Farther east the southern shore of the lake appeared to consist of a flat, barren sedimentary plain, which stretches right away to the mountainous mass G2, this being an advanced portion of the range between the two lakes; indeed it appeared, so far as could be judged from the distance, to advance all the way to the shore, and to terminate abruptly in the lake. On our left we had a similar sedimentary plain, extremely flat and level, and barren, with an occasional minor promontory and litoral lagoon. This, owing to its shape, compelled us to steer first north and afterwards west. There was a gentle breeze from the east-south-east, and during the greater part of the day the weather was so far peculiar in that, while it was warm and sunny on the lake, heavy clouds hung over the country to the west and time after time discharged their contents earthwards. The caravan, whilst marching along that side of the lake, encountered several showers of hail. The lake was lifeless and monotonous, there being nothing to break the uniformity except long, white strips of foam and gulls hopping about on the promontories. After we had got outside the bay the water became perfectly clear. As far as the promontory at which we turned northwest I took the following soundings — 2.98, 3.15, 2.89, 3.12, 3.22, 3,08, 1.63, 0.62 m., this last close to the promontory, and for a long way outside the bay the lake is shallow. Along the stretch to the next mud promontory the following two soundings were taken — 2.98 and 7.20 m., and after that the water became shallow.
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