elevation increases till they attain the limits of perpetual snow at the sources of the Etsina-gol[1] and Tolai-gol. Here all these ranges may possibly unite or throw out new branches, but in any case further to the west they again diminish and soon terminate, perhaps merging in the general upheaval of the Gobi.
The whole of this mountainous system is known to the Chinese under the name of Siue-shan or Nan-shan; but the several ranges have no special names, and, therefore, for the sake of distinctness I will use the terms 'northern' and 'southern' for the ranges on either bank of the Tatung, while that dividing Ala-shan from Kan-su shall be called the 'border range,' without, however, the least intention of applying these names in the future.
The northern and southern chains bear a close resemblance to each other, and are equally wild and alpine; they abound in deep narrow gorges, huge cliffs, and precipices. About the middle of the Tatung-gol a few solitary peaks rise to a height of 14,000 feet,[2] but without attaining the perpetual snow-line. The snowy mountains are, as we have mentioned, further to the west, near the towns of Lang-chau and Kan-chau, and at the sources of the Tatung and Etsina. One snowy peak, however, rises behind Si-ning.
Although the pass over the northern chain is
