The camp just mentioned, the altitude of which was 4,609 m., stood 4o to 5o m. above an oblong or oval-shaped lake situated in the middle of the latitudinal valley. This lake was said to be called the Dagtse-tso; its eastern end was a few kilometers to the north of our camp. It forms the predominant feature in the scene, and north-west of it several lofty summits towered above the mountain-range that rises in that quarter. In shape this new lake is very unlike those we had recently been travelling amongst. In the case of the latter the mountains advance quite close to the water's edge, and even rise out of it in the form of islands ; whereas the Dagtse-tso is certainly a very shallow sheet of water, and it lies at a great distance from all the surrounding mountains, and has flat, rounded shores, above which it was easy to see, even from a distance, distinct traces of an older, higher beach-line and proofs that this lake, like the Selling-tso, is undergoing a process of desiccation. But the process appears to be going on at a more rapid rate in the Dagtse-tso than in the Selling-tso. At the eastern end of the former we counted eight distinct chains or rings of lagoons, arranged concentrically and forming long, narrow sheets of water, interrupted at intervals, the yellow colour of which contrasted with the pure blue water of the lake. It is abundantly clear, that these collections of water are dammed up by older strand-ramparts, and that they are fed by springs close at hand. Seen from a little distance, these lagoons present a rather unusual appearance ; surprise is created not only by their irregular position and structure, but also by the fact that all of them, the lowest as well as the highest, are able to contain water. Pl. 66 of my atlas will give an idea of their arrangement. The positions, with intervals of almost equal distance between the broken rings, point to a regular progressive rate in the shrinkage of the lake. There are also lagoons and ancient beach-lines on the southern shore of the lake; but they are of quite a different character, being smaller, more scattered, and not concentrically arranged, parallel with the shore. It is worth noting, that these strand-ramparts are especially developed at the eastern end of the lake, that is to say at that end upon which the waves beat with the greatest violence, driven as they are by the prevailing westerly winds, and consequently at that part of the lake in which the strand-ramparts are being built up with the greatest degree of energy.
September 26th. From Schalung we travelled towards the west-south-west, keeping a couple of kilometers from the southern shore of the lake. The little red detached range soon came to an end, and in place of it we had on our left hand a bigger and more accentuated range, situated farther to the south. In the entrance to its transverse glens freshwater springs not seldom leap out, though the yield of water is small. It was in their vicinity that the i 6 nomad tents stood which we observed on this day's journey. We left close on our right hand several freshwater pools, some containing muddy yellow water, others water that was of perfect limpidity. The country between our route and the lake was level, and abounded in pools and marshes; it was with the very object of avoiding this marshy and treacherous ground that we travelled at such a distance from the lake. The shore-line is regular, possessing neither bays nor promontories. The water was rather salt, its sp. gr. being 1.043. Notwithstanding the proximity of human
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