THE INFLUENCE OF THE HIMALAYAS 55
ter of fact, the valleys of both rivers here take the form of narrow gorges, which can be traversed only with the greatest difficulty. Hence at Kurgil the road turns to the southeast, leaving the larger valleys, and for forty miles lies almost parallel to the Indus, keeping ten or twelve miles away, above the heads of the short tributary gorges, and crossing two easy passes over 13,000 feet high. Apparently, the deep, narrow character of the lower reaches of the Dras, Indus, and other rivers indicates that the Himalayan region, as a whole, has been recently uplifted in such a way as to accelerate the main river and cause it to carve a deep canyon. Naturally the tributaries have followed suit, much to our inconvenience, and have converted the lower parts of their valleys into narrow gorges, although the process of deepening has not yet had time to reach the upper parts. Thus the warping of the earth's crust and the last phase of the uplifting of the Himalayas, though they took place long before the earliest recorded human occupation of the country, have had a very recognizable effect upon man. The process has not only raised the upper Indus valley to a greater elevation and intensified its Alpine character, but it has increased the isolation of the country. It has made the main passes higher, more snowy, and more difficult to cross; and has obliged every traveler to Ladakh to traverse two minor passes, instead of going down the Dras and up the Indus. The Dras River is typical of Ladakh. The Indus and most of its tributaries have three distinct parts like the Dras, — at the head a broad, glacial valley, smooth and easy to traverse, but cold and almost uninhabitable; in the middle a narrower valley, rendered habitable by its lower altitude and
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