The Tuna Plain is like the Palmyra Desert at the point where one comes within view of the snows of Lebanon. It is not monotonous; there is too much play of light and shade for that. Everywhere the sun shines, the mirage dances; the white calcined plain becomes a flock of frightened sheep hurrying down the wind; the stunted sedge by the lakeside leaps up like a squadron in ambush and sweeps rapidly along without ever approaching nearer. Sometimes a herd of wild asses is mingled in the dance, grotesquely magnified; stones and nettles become walls and men. All the country is elusive and unreal.
A few miles beyond Guru the road skirts the Bamtso Lake, which must once have filled the whole valley. Now the waters have receded, as the process of desiccation is going on which has entirely changed the geographical features of Central Asia, and caused the disappearance of great expanses of water like the Koko Nor, and the dwindling of lakes and river from Khotan to Gobi. The Roof of the World is becoming less and less inhabitable.
From the desert to Arcady is not a long journey, but armies travel slowly. After months of waiting and delay we reached the promised land. It was all suddenly unfolded to our view when we stood on the Khamba la. Below us was a purely pastoral landscape. Beyond lay hills even more barren and verdureless than those we had crossed. But every mile or so green fan-shaped valleys, irrigated by clear streams, interrupted the barrenness, opening out into the main valley east and west with perfect symmetry. To the north-east flowed the Kyi Chu, the valley in which Lhasa lay screened, only fifty-six miles distant.
To the south of the pass lay the great Yamdok Lake, wild and beautiful, its channels twining into the dark interstices of the hills--valleys of mystery and gloom, where no white man has ever trod. Lights and shadows fell caressingly on the lake and hills. At one moment a peak was ebony black, at another--as the heavy clouds passed from over it, and the sun's rays illumined it through a thin mist--golden as a field of buttercups. Often at sunset the grassy cones of the hills glow like gilded pagodas, and the Tibetans, I am told, call these sunlit plots the 'golden ground.'