to disgust anyone; but we, like the Mongols, were obliged to use it, taking care to boil it first and to add brick-tea.
The mirage, that evil genius of the desert, mocked us almost daily, and conjured up such tantalising visions of tremulous water that even the rocks of the neighbouring hills appeared as though reflected in it. Severe heat and frequent storms of wind prevented our sleeping quietly at night, much as we needed rest after the arduous day's march.
But not to us alone was the desert of Mongolia an enemy. Birds which began to make their appearance in the latter half of August suffered equally from thirst and hunger. We saw flocks of geese and ducks resting at the smallest pools, and small birds flew to our tent so exhausted with starvation as to allow us to catch them in the hand. We found several of these feathered wanderers quite dead, and in all probability numbers of them perish in their flight across the desert.
The chief migration of birds was in September,[1] and by the 13th of that month we had counted twenty-four varieties. From our observations the geese directed their flight not due south but south-east towards the northern bend of the Hoang-ho.
Eighty-seven miles north of the Hurku hills we crossed another trade route from Kuku-khoto to Uliassutai;[2] practicable for carts although the traffic
