early in the fifth century A. D. is too scanty to permit of any definite opinion being formed as to the racial composition of the people from that region to whom the Chinese in the 3rd-4th century A. D. continued to apply, in a quasi-archaic fashion, the designation of ` Great Yüeh-chih '. So much, however, is clear that as long as the inroads of the Huns established north of the Tien-shan remained a constant danger to the northern oases of the Târim Basin and the great route leading through them, Chinese political wisdom could not fail to realize the advantage of enlisting troops from the powerful western neighbours whom the common danger threatening from the Huns was likely to make trustworthy. This expedient was bound to recommend itself particularly in view of the unwarlike character which the population of the Târim Basin seems to have borne, then as now, and of the complications likely to arise from those internal intrigues and rivalries which the Later Han Annals prove to have been so frequent in the ` Western Countries '.2° The tradition established by such a system is likely to have continued into Chin times, even after the danger from the Huns had receded, and amply suffices to explain the appearance of Indo-Scythian mercenaries so far away to the east. It should be noted that we meet with references to individuals of Great Yüeh-chin' origin also among the approximately contemporary Chinese records found at the Niya Site."
But it is only indirectly that, here and there, some evidence of Chinese Central-Asian policy can be traced in the office records which survived at the Lou-lan station. The military incidents they mention mainly concern petty cases of individual soldiers. Thus the report contained in No. 764 accuses an officer of culpable negligence for not having accompanied a certain unhappy soldier who, in consequence, fell into the water and was drowned. No. 763 acknowledges the receipt of a verbal order, brought by a barbarian soldier, for an advance to be made. Elsewhere we learn of men who have 'escaped en route (No. 815), or we are furnished with details as to a barbarian soldier's kit including a felt dress, etc., as recorded on a slip which shows signs of having been attached to a parcel (No. 804 ; also 832).
Whatever the explanation may be, we find few indications of trade passing through the station at that period. A tribute in silk pieces sent by a certain barbarian is specified in No. 903, and the references to fabrics in Nos. 805, 812, 814, probably concern the same staple commodity. Transport by camels and donkeys seems to be alluded to in Nos. 839-41 ; the inspection of a cart and bullocks at a camp is mentioned in No. 755.
The paucity of references to trade is set off, to some extent, by the evidence which the remains of private letters supply as to continued intercourse towards the east and the west. It is worthy of note in passing that all documents which can safely be recognized as private letters appear to be written on paper, a circumstance to be accounted for on the one hand by the greater convenience of the new writing material, and on the other by the less conservative ways of personal as compared with official correspondence. In No. 912, a letter dated A. D. 3121 the writer mentions departure from the Yü-mên kuan, or Jade Gate barrier, which was situated, as we shall see, on the direct route towards Tun-huang. No. 918 is a letter dated from Tun-huang itself, and No. 914, the fragment of another, mentions trade at Tun-huang. In No. 923 we seem to have the remnant of a letter addressed to a traveller making his way to the ` Western Countries ' by a person left behind in the east.
When we turn to letters evidently written from the west; it is interesting to find the affairs of Yen-ch`i or Kara-shahr repeatedly referred to. In No. 93o a certain Hsüan, a native of Yen-ch`i,