operations were issued to the soldiers from a central store is definitely proved by inventories of hoes, spades, saws, etc., as contained in Nos. 779-81, 787, 791, 891. In the first-named of these documents the designation of ' barbarians' hoes ' may Well refer to the broad-shouldered hoes known as ketmaus which are now used everywhere throughout the Tarim Basin by the local cultivators but unknown to the Chinese agriculturists.
The importance which the proper maintenance of canals and of dykes intended to feed them must have possessed for the colony need not be specially emphasized. We find evidence of it in several documents. A prefect of water, corresponding to the present ' IVITrab Beg ' of a Turkestan oasis, is mentioned in No. 888 in connexion with a requisition for ropes. No. 761, unfortunately fragmentary, is of interest as reporting on the condition of an irrigation embankment which is stated to have been breached in six places and to have been overflowed by the water. The report is an apt illustration of the danger which always threatens agriculture in the low-lying deltas of Turkestan rivers. On the other hand, the mention of five hundred and one men being at work on the embankment shows that the resources of labour for coping with this risk were not altogether insignificant. In No. 754 the return of a certain soldier charged with watching a dyke is urged. Of another risk, very different in character and yet in its origin connected with the same deltaic conditions, we obtain a glimpse in No. 750. In this letter a certain Chao Pien, who styles himself an assistant to the prefect, reports that the guardians of the flocks passed the night south of the town and on a certain date reached water. It appears to have been a case when particular tracts of riverine jungle had become useless for grazing, owing to the water-supply running dry in consequence of a diversion of the river channel, and the flocks had to be sent some distance in search of sufficient water.
That the peaceful preoccupations of those in charge of the colons did not altogether efface its military character is shown by documents, of which Nos. 758, 775-77, 794, are examples, containing reports on arms such as cross-bows or sword-blades no longer serviceable, on leather pieces prepared for armour and helmets, and on brass rings for securing prisoners. The numerous inventory records, etc., referring to medicines, No. 782-85, 790, 795-96, are also likely to have come from some military store-keeper's office, in view of what subsequent finds have shown us about the medical care taken of the soldiers along the Tun-huang Limes.16 It is of some historical interest to note that in a number of cases where individual soldiers are specified we find them described as ' barbarians ' or Ili (see Nos. 763, 804, 844-46, 892), and that all those whose nationality is exactly indicated are stated to be [Ta Yiieh]-chip t, i.e. Indo-Scythians.17 We may safely conclude that of the mercenaries employed under Chinese officers at this station, and probably also at other and more important garrisons of the ' Western Kingdoms ', a considerable proportion was drawn from that foreign nation which in Chinese eyes had the merit of representing the descendants of the hereditary foe of the Hsiung-nu or Huns.
A well-known record of the Former Han Annals tells us how the ' Great Yüeh-chih', the later Indo-Scythians, had been driven by the Huns in the second century B. C. from the plains north of
the Nan-shan, first to Sogdiana and thence to the region of the Middle Oxus, the ancient Bactria and later Tokharistan.18 It is there that the Later Han Annals place the main seat of their power
even after their conquests under the Kushan dynasty had extended south of the Hindukush and into the North-west of India.19 Our knowledge of the conditions in which the Great Yüeh-chih dominion on the Middle Oxus maintained itself until the advent of the White Huns, or Ephthalites,
18 See below, chap. xx. sec. vi. 18 Cf. Specht,,Journal Asiat., 1883, ii. pp. 320 sqq.
17 Cf. M. Chavannes' note, Documents, p. 178, note on 79 See Chavannes, Les pays d'occident, T'oungpao, z907,
No. 846. p. 189, note.