A new important addition to our knowledge of the lakes was given by Sir RICHARD STRACHEY in the narrative of his journey in September 1848, which he accomplished in company with Mr J. E. WINTERBOTTOM. The results were published in full more than fifty years after his journey.' He started from Milam and took the road of Topi Dunga, Laptel, Shangcha, Tisum, from where he emerged on the plain of Guge. In the upper part of the valley of Gori he came upon the base of the great fossiliferous series of rocks which constitute the ranges over which the passes into Tibet are situated. Richard Strachey called this line of elevation the Indian Watershed of the great Tibeto-Himalayan tableland. At Tisum he found that the plain of Guge appeared to be quite flat and open for some r o miles to the north, but it ended abruptly on the south. The Jankum river had cut out a huge furrow from the plain with sides sloping about 45°. The ravines, 200 or 300 feet in depth, opened up sections of the plain showing that it consisted of a great deposit of gravel and boulders and sand. The surface of the plain was found to slope towards the Satlej and the beds were deposited parallel to the surface. As he descended he found that the alluvial beds rested on shales and shaly limestones which generally dipped to the N. W. Boulders and pebbles in the river bed consisted mostly of calcareous rocks but a notable proportion were composed of porphyries, only one or two specimens of granite being seen. In the shales near the Satlej he found an Ammonite and Inoceramus showing that the strata were either Jurassic or Cretaceous.
He deals with the hot springs of Tirtapuri and Kiunglung, although he did not visit them personally. On the road from Ligchephu to the Darma Yankti he finds a great difference between the rivers in the eastern and western parts of Guge. The western flow in very deep ravines, whereas the eastern are shallow, about 25 feet only below the surface of the plain. This difference he finds to depend upon the increasing depth of the bed of the Satlej on its way towards the west and upon
I »Narrative of a journey to the lakes Rakas-tal and Manasarowar in Western Tibet.,' Geographical Journal, Vol. XV, Febr. 1900, p. i 5o et seq., March, p. 248 et seq, and April p. 394 et seq.
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