fossil, and that points to a fresh-water origin rather than a sea.
In area the Gobi Desert is about 480,000 square miles, extending about 1000 miles from east to west, varying from 450 to 600 miles from north to south. It has no permanent streams, the north-west winds of winter having discharged their moisture on the Sayan slopes, and the south-east winds of summer having exhausted their humidity on the Khingan and In-shan heights. The temperature varies from the cold of Siberia to the heat of India, changes of temperature being exceedingly sudden, one traveller recording 68° Fahr. in the shade in the day and —18° Fahr. the same night.
On the east of the Gobi the Khingan mountains with their parallel ridges constitute a zone of nearly 100 miles wide, by which the Mongolian plateau drops south-east towards the lower plains of Manchuria. To the north-west of this zone there is another band of undulating tableland about 100 miles wide, well watered and well wooded.
In consequence of the altitude of the east of Mongolia, the Khingan mountains appear only about 1500 feet high on their western side, but much higher from the Manchurian aspect. The In-shan, in consequence of the plentiful supply of rain brought from the Gulf of Pechihli, are well wooded, though the Chinese are denuding these forests rapidly.
The Ordos, while physically and ethnically belonging to Mongolia, is separated from that country by the great sweep of the Yellow River. It is about 40,000 square miles in area, and has a mean elevation of 3500 feet, and is more arid than Mongolia. Jenghis Khan and some members of his family are reported to have been buried here. Although now one of the most inhospitable regions of the Gobi, there are evidences of buried cities and an earlier prosperity.
The Great Wall, which forms the southern boundary of Mongolia, has a total length of about 2000 miles, and is said to have a cubic capacity of four thousand millions of
