スウェン・ヘディン Through Asia の一部を書写したので紹介する。
Up the Alai Valley
Before I proceed with my itinerary, I should like to say a few words about the Alai valley, the huge trough-like depression which separates the Alai chain from the Pamir plateau. Bounded on the north by the Alai Mountains, and on the south by the Trans-Alai , it is terminated at its eastern extremity by the massive mountain-knot of Mus-tah-tau. Thence it stretches seventy-five miles westwards, and is continued in the valley of Lara-technical. It’s breadth varies from three to twelve miles; the altitude sinks from 10,500 feet in the east to 8200 feet at Dariut-kurgan in the west. It is drained by the Kizil-su , which traverses it throughout its entire length, gathering up on the way the rainfall of the surrounding mountains. After quitting the Alai valley, the river enters the valley of Kara-teghin, winds through it under the name of the Surkhab, and finally joins the AMU-daria, bearing a third name, the Wakhsh, at the point of confluence.