Sec. ii] FROM THE INCHIKE RIVER TO KUCHA 1237
Chinese commander Chêng Chi formed a military encampment with 1,5oo Chinese troops in Ch'u-li, and during the following years made this territory his base for a series of successful operations against Chu-shih, or Turfân, which led to the complete subjugation of that state and even to the extension of Chinese control over the 1-Isiung-nu tribes immediately to the north-east of it.9 In recognition of these achievements Chêng Chi was in 6o B. c. made the first ' Protector-General ' (Tu-hu 411S 0), and as the Cli`ien Han shu places henceforth the seat of this chief political representative of the Empire in the Western regions at Wu-lei, north of Ch`u-li, i.e. at Yangi-hissar or Chalk," it is reasonable to assume that the selection of this particular locality was dictated by its vicinity to Ch`u-Ii, the original base of Chêng Chi's far-reaching activity.
In view of what has been explained above as to the physical drawbacks to permanent settlement in the riverine tract represented by the ancient Ch`ii-li, it might appear difficult at first sight to account for the importance which the Chinese evidently attached to its colonization during those early operations. In reality it must have been mainly due to the advantageous position which the tract occupies relative to the great Chinese road via Lou-late, the ancient ' Northern route '. From the map it is easy to see that this small Mesopotamia lies on the most direct line connecting Lou-lan with Kuchd• and the other main oases westwards. Through it passes also the nearest route for reaching the latter from the present Lop region or Shan-shan, a route still regularly used for caravan traffic at the present day. This point must have claimed all the more attention because we know that Chêng Chi was charged also with the protection of the ' Southern route' passing through Shan-shad westwards." Finally it should be noted that Ch`ü-li supplied a more convenient base for operations towards Kara-shahr and thence towards Turfân than Lou-lan could ever have done. Lou-lan lay far away from the small states in the Tarim Basin upon which the Chinese had to depend for their auxiliary forces, and was separated from Turfân by the great barren plateaus of the Kuruk-tagh, a formidable obstacle in the matter of supplies and transport. The very fact that Ch`ü-li held only a very thin indigenous population, while potentially fertile lands were abundant, may have furnished an additional reason for choosing it for a military colony.
But however this may be, the drawbacks presented by nature on ground where river-beds are constantly shifting and canals, whether for irrigation or drainage, most difficult to maintain must have soon made themselves felt there quite as much as they would nowadays. It is to them, I believe, that we may safely attribute both the selection of Wu-lei for the Protector-General's seat from 6o B.C. onwards and the complete disappearance of CI-Ai-1i from the later Chinese records. Neither in the Later Han Annals' account of the Western regions nor in that of the Wei lio do we find the territory mentioned again under that or any other name. Its importance for the Chinese had evidently been ephemeral. What with this and the destruction inseparable from constant riverine changes, the total absence of ancient remains in this region can in no way cause surprise.
SECTION III.—THROUGH THE TAKLAMAKAN TO KARA-DONG
My stay at Kuchâ, which I reached on January 17, was bound to be short and busy. It was there that I finally had to settle all plans and arrangements for the journey which was to take me right through the whole width of the desert basin to the southern edge of the Taklamakan. Already,