the forests have all been swept away, and the few streams quickly lose themselves in the ground. Over most of the seven hundred miles between Kalgan and Urga there are no trees save half a dozen scrub elms, and the only rivers are the Sha Ho, or "Rivers of Sand." But the grassland, after the summer rains have set in, is like the rolling prairies of the West, and even in Gobi there are only about fifty miles quite without vegetation. Elsewhere there is a sparse growth of coarse scrub broken by stretches of rock and sand.
In crossing Gobi one sees here and there a marsh or shallow salt lake, telling of a different climate in a bygone time, but to-day the passing caravan depends on wells of varying depth, and found at irregular intervals,—ten, twenty, even fifty miles apart. They date back beyond the tradition of living men, and each has its name and character. In some the water is never-failing, in others it quickly runs dry. Occasionlly it is slightly brackish, but usually it is clear and cold. Without these wells the three hundred miles of Gobi would impose an almost impassable barrier between North and South Mongolia. As it is, the desert takes its toll from the passing caravan; thirst, hunger, heat, and cold count their victims among the animals by thousands, and the way is marked by their bleaching bones.
This great, featureless, windswept plateau keeps