国立情報学研究所 - ディジタル・シルクロード・プロジェクト
『東洋文庫所蔵』貴重書デジタルアーカイブ

Sec. i] THE EXTENSION OF THE `GREAT WALL' BEYOND TUN-HUANG 725

have played a prominent part in the operations which resulted in the progressive settlement of Chinese military colonies along the great highway towards Tun-huang and the Tarim Basin.9 The

development of the new territories soon after led to the separate command of Wu-wei   g being
created in what is now Liang-chou. In III B.C. these two commands were again subdivided by

the establishment of the commands of Chang-yeh   , the present Kan-chou, and Tun-huang
--1 a. In 119 B. c., as we are told by the Ch`ien Han shu, the Chinese had already passed to the north of the Huang Ho and established irrigation works and military colonies, to the total strength of fifty—sixty thousand men, as far west as Ling-chü r gx. This locality corresponds to the present Ping-fan 211 #, a sub-prefecture on the high road leading from Lan-chou towards Liang-chou. It is from this point onwards that the construction of a wall extending to the west is distinctly recorded in Chapter xcvi of the Former Han Annals, immediately after the first conquests of 121 B.C.70

The Annals do not inform us as to the exact line which this earliest portion of the western extension of the ' Great Wall ' followed, and in the absence of archaeological evidence it would be useless at present to attempt conjecturally to trace it as far as Mao-mei, on the Etsin-gol. This was the easternmost point up to which I was able to explore the ancient Han Limes in 1914." But there can be no doubt that its main purpose was to protect the great highway opened for trade, and soon also for political expansion, into Central Asia. It is equally obvious that this Limes was also meant to assure more safety to the military colonies which were planted in the submontane tracts traversed by the great route. Their agricultural produce was essential for making this long line of communication practicable for trade caravans and troop movements. The wall of the Emperor Wu-ti was thus distinctly intended to serve as the instrument of a ' forward policy' conceived on a big scale, and the analogy it thus offers to the earlier Limes systems of the Roman Empire is most striking ; for it is a fact well established by modern antiquarian researches that the lines of the Roman Limes were originally integral portions of the great strategic road system of the Empire. That the word limes served as the technical term for military roads pushed forward from a base of operation seems to me the best justification for the use I have made of it throughout to designate this western extension of the Chinese Great Wall.12

The Chinese historical sources do not inform us of the progress made or the successive stages reached by the Emperor Wu-ti's extension of the wall before the year to8 B. C. At that time we are told that ' a continuous line of posts and small forts was established from Chiu-ch`üan or Su-chou as far as Yii-nrên, or the Jade Gate '.13 This record at once raises the question as to the position

Western extension of 'Great Wall' to serve Chinese forward policy '.

Line of posts and forts established to

Yit-mtn.

9 Cf. Wylie, J. Anthrop. Inst., x. p. 22 : ' The region of Chiu-ch'tian was first established, and afterwards gradually the people were removed in to fill it.'

70 See Chavannes, Documents, p. vi, note I ; Wylie, J. Anthrop. Inst., x. p. 22.

" See Third journey of Exploration, Geogr. Journal, xlviii. p. 296. The line of the wall which our modern maps mark, in a fashion not always consistent, as running from Lan-chou to Su-chou, more or less parallel to the high road and to the north-east of it, may safely be assumed to be of the same late mediaeval origin as the wall I examined for considerable stretches between Su-chou and Kan-chou in 2907 and 1914 ; cf. Desert Cathay, ii. pp. 275 sq., 336; Geogr. Journal, xlviii. p. zoo; Maps Nos. 88, 91, 93, and below, chap. xxvti. sec. ii, iv. But later as this wall undoubtedly is and purely defensive in character, yet it helps to illustrate the importance which Chinese policy continued to attach to the safety of these

advanced north-west marches of Kan-su, even after its control of the Tarim Basin had long ceased.

" For a very lucid and comprehensive review of the principles underlying the earliest Limes constructions under Augustus and Tiberius, cf. Prof. E. Kornemann's paper Die neueste Limesforschung , in Klio, vii. (r 907) pp. 76 sqq. For detailed evidence the authorities quoted there in the notes may be consulted. Here the briefest reference must suffice to such significant terms in the classical authors as limitem agere, mitem aperire for the opening of such strategic routes; castra in limile locare, etc.

It is clear that the military roads guarded by a continuous chain of posts, such as modern policy on the Indian North-West Frontier has found it necessary to push forward, e.g. through the Khyber and up the Kurram, Tochi, and Gomal valleys, fully deserve to be considered as limites.

" Cf. Chavannes, Documents, p. vi, note 3, where the