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fications of the mountains, but the differences of altitude between the bottoms of the glens and the cols were very slight and the slopes were flat. To the east we perceived several dominating peaks, one or two of them with snow. All these belong to the main range that borders the next latitudinal valley we should come to. After passing a pool, we crossed over yet two other small cols, the higher of which reached an altitude of 5112 m., this being the last in the series, and after that we definitively descended the northern slopes of this broad flat main range. From the top of the last pass we commanded a splendid view of the next latitudinal valley; it appeared to be bounded by low hills on the north. This new valley was hard and excellent to ride upon. It lacked however a main stream, having nothing but small, dry watercourses running now in one direction, now in another, so that it was almost impossible to tell which was the lowest part of the valley. Judging from the last watercourses that issue from the red mountain range, the fall is towards the east. In both that direction and in the west the country was quite open to the far off horizon. In the middle of the latitudinal valley were some solitary blocks of schist; and some of the small pools it contained had white rings round them, pointing to the presence of salt. The surface was perfectly sterile until we reached the first foot-hills on the north side of the valley. There we hit upon a freshwater pool, with a thin sprinkling of grass round it; the pool must plainly be fed by springs and must possess a subterranean outlet, for there is no visible emissary flowing out of it. The altitude of Camp LVIII was 4991 m. and of the bottom of the valley 4988 m.
Thus the character of the country had in the course of the day essentially altered. Not only were the mountains lower than heretofore, but the surface was again barren. For 3o km. we did not find a blade of grass, and only once a little moss amongst the gravel. The consequence was an entire absence of game. Even ravens, which never fail in other parts, were here wanting.
Immediately north of Camp LVII the red sandstone dipped clearly i o° towards the N. 70° W. At the base of the terraced bank of the first large stream flowing towards the east the same rock cropped out at 54° towards the S. 60° E., but here it was excessively brittle and weathered. At the same place we found gypsum, and again a little farther on, in thin bright laminae, embedded in the sand and soft disintegrated débris of the red sandstone. The entire country hereabouts was of a brick-red colour — the ground, the hills, the mountain crests, all alike were red, except for an occasional small patch or strip of white, indicative of salt or gypsum, but not of snow.
A little farther north we came across a very hard, fine-grained, dark crystalline schist, containing veins and dykes of lighter and coarser crystallised rocks; its dip appeared to be 83° N. North of that again was a dark argillaceous schist, very much weathered and very friable, and split into thin lamine with a dip of 48° S. In the upper part of a series of small, low detached heights, which projected above the ground in a glen, there cropped out a yellow variety of rock, brittle and very friable; and finally the schist appeared once more, dipping 71° towards the S. 8o° W.
Thus the southern parts of the main range that we had just crossed over consist of red sandstone, while its northern parts are composed predominantly of
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