418 ACROSS THE DESERT TO TARIM CH. XXXvI
which we were traversing had its bounds. After half a mile the closely packed ridges of sand gave way to a wide expanse of flat ground evidently eroded. It showed a soft surface as if of disintegrated clay or loess, and over extensive patches was thickly covered with snail - shells. I had often before noticed the latter embedded in the layers which erosion had exposed on the slopes of Yardangs ; but nowhere yet had I seen these proofs of ancient fresh-water marshes or lakes spread out so uniformly and in such profusion. Erosion during long ages seemed to have done its work of levelling so completely here that but few Yardang ridges had escaped. They rose island-like among low dunes (Fig. 127). About three and a half miles from camp we came upon a grove of dead Toghraks, surrounded by dunes rising to about thirty feet.
At two points beyond, each three to four miles farther, we found our route crossed by continuous ridges of sand, like the Dawans of the Taklamakan, rising to about fifty feet above the flat eroded expanse (Fig. 128). But otherwise the latter continued and offered relatively easy going. My satisfaction at this was, however, soon damped by the observation that after the patch with dead Toghraks above mentioned the remains of ancient trees completely disappeared. The ease with which we had so far been able to obtain fuel, and the need for keeping the camels lightly laden, had made us overlook the necessity of being prepared for this emergency. I got the men to pick up carefully in bags every scrap of decayed wood débris we could sight. But the total crop thus gathered weighed only a few pounds when dusk began to descend.
It was a bad outlook for the night, the last of the year 1906, and though I was glad to spend it in the solitude and peace of the desert, the prospect of having nothing to prepare warm drink and food with was distinctly unpleasant. How should we fare in the bitterly cold nights still to be faced before we could strike the jungle belt of the Tarim ? I had resigned myself to a fireless camp after a fourteen miles' tramp with the wearied camels when, from the height of a curious eroded clay ' witness ' rising to twenty-five feet or so between low dunes, I spied a small darkish cone.
IIIFカラー高解像度
