352 THE PULSE OF ASIA
canals. They were located on the mountain sides at an elevation of from 10,000 to 10,500 feet above the sea. As we concluded at the time : " They must be hundreds, possibly thousands, of years old, since they are thoroughly graded, and are sometimes wholly obliterated for a space. They cannot be of extreme age, however, for many can still be traced throughout their entire length, although they lie across slopes of considerable steepness, where erosion is so rapid that such small features must soon be eradicated. They must be irrigation canals, for they contour around the hills, are broad enough to carry most of the water of the streams from which they diverge, and come to an end in places suitable for fields. The peculiar feature is that they lie at a great altitude, where there is now no agriculture, nor could be, it would seem. Snow falls at Son Kul, so the people say, during all but two months of the year. On the morning of July 8, at the altitude of the upper canals, I walked on new snow which was said to have been a foot deep a few days before. The next morning, near the shore of Son Kul, below the level of the fields once watered by the canals, the ground was stiff with frost, and the little pools on the edges of the brooks were skimmed with ice. Moreover, if agriculture were possible under such conditions, irrigation seems unnecessary. In July, the ground was saturated with moisture, and the natives told us that the grass is always as green as when we saw it [in summer, at least]. The simplest hypothesis is that at some time since the human occupation of the country, the climate was warmer, and therefore drier than now, but this cannot be proved. In regions such as Transcaspia and Persia, there is strong evidence of a greater water supply
IIIFカラー高解像度
