Two days' march from the residence of Tsing-hai-wang we left the mountains behind us. As we crossed the last spurs of the southern range we saw stretching before us the level plain of Tsaidam,[1] bounded on the north, east, and south by mountains,[2] but extending westwards in one continued expanse, as far, according to the natives, as Lake Lob-nor.
The plain of Tsaidam, which at a comparatively recent geological age formed the bed of a huge lake, is now covered with morasses, so thickly impregnated with salt as to be encrusted with a layer in some places half-an-inch to an inch in thickness, resembling ice. Here too are shaking bogs, small rivers and lakes; and in the western part of the plain the large Lake of Kara-nor. The most important of its rivers is the Baian-gol, about 1,600 feet wide where we crossed it, but of inconsiderable depth, in fact, not more than three feet, with a soft slimy bed. According to the Mongols the Baian-gol flows out of Lake Toso-nor at the eastern extremity of the Burkhan Buddha, and after a course of about 200 miles loses itself in the marshes of Western Tsaidam.
The saline argillaceous soil of this region is ill-suited to vegetation. With the exception of a few kinds of marshy grasses, which in places grow together and form meadows, the whole expanse is
