ground which looked old, and when I inspected these on June 20, I soon found conclusive evidence proving that they belonged to the line of the Limes.
The westernmost of these towers lies about 4 miles in a straight line to the south-west from the temple outside the west gate of An-hsi, which served as our quarters. It is situated in the broad belt of waste ground which I have mentioned already as extending from east to west between the cultivation areas near Kua-chou-ch`êng and An-hsi.3 The tower, though badly decayed, still rises to a height of about i8 feet, on a base which erosion has reduced to about 14 feet square. In construction it shows, like the other ruined tower, closest agreement with the methods so familiar to me from the Limes remains in the Tun-huang desert, solid layers of stamped clay being used with an inner framework of Toghrak posts. The fact that. in spite of having been cut right through in the centre from east to west by sand-scouring, it still stands upright is the best proof of the solidity of construction. Dark-grey potsherds of the Han type, showing mat marks, lay around the foot of the tower and attested its antiquity.' The same were found also on a low mound, about 32 feet long and half as wide, which adjoined on the south and contained the foundations of walls built with sun-dried bricks, evidently of quarters. No other remains survived on this ground exposed both to wind-erosion and to moisture.
But as I proceeded to the next tower about a mile off to the east, the soil turned from scrub-covered loess to fine gravel bearing only scanty vegetation, and here from about half-way onwards the straight mound marking the direction of the ancient border wall could be traced quite clearly. It rises to a height of about 4-5 feet, and, where a cutting was effected close to the eastern tower, proved to contain irregular layers of Toghrak branches embedded in gravelly earth. This tower is in better preservation, standing to a height of 22 feet on a base about i7 feet square. Here, too, broken Han pottery was picked up at the foot of the tower as well as on a clay mound about 55 yards off to the south. This mound measures about 28 by i 6 feet and rises to circ. 8 feet above the level ground. The clearing of its top and slopes only yielded more remains of pottery of the Han type besides layers of decayed straw. From this point the straight line of the wall was traceable eastwards without any difficulty over most of the distance, about i â miles, which lies between the tower last mentioned and the high-road to An-hsi. The ground here consists of bare gravel, and to this fact, no doubt, the preservation of these traces of the Han wall is due. Elsewhere to the east and west of the stretch described it is scrub-covered loess, where moisture and vegetation were bound to destroy the remains of the agger much more effectively. When revisiting this ground in October, 1907, I found in fact considerable portions of the scrubby waste west of the cart road flooded from the spillage of canals.
Where the line of the Limes strikes the main road from Tun-huang to An-hsi there stands a much-restored tower built, with its modern outer masonry of vertically placed bricks, in the usual shape of a truncated cone.& Immediately adjoining it on the south is a small reception-hall such as is invariably to be found at points some distance from district headquarters where Chinese etiquette demands that officials arriving or parting should have their formal welcome or farewell, with tea, etc., by the roadside. There, too, rise five small towers in a row, the regular mark of the usual main stages on Chinese high roads. That the core of the large tower, standing exactly on the line of the
$ For the exact position of these Limes remains, see Map No. 81. D. 2.
' The following are specimens, of such potsherds :
. An•hsi. ow. Fr. of pottery, hand-made, of grey clay, the outer surface flared to light red. Fired on an open hearth ; flat, like a tile. Gr. M. 3".
An•hsi. 002. Fr. of pottery, hand-made, of fairly welllevigated clay, dark grey, burning to dull red; fired on an open
hearth; outer surface blackened by smothering' ; mat-marking outside. Gr. M. 2".
5 The tower is marked on Map No. 81. n. 2 with the name Wei yilan-tun. The word tun ja is regularly applied on the Kan-su marches to P'ao-Cais or watch-towers. If We:. yUau is here the well-known Chinese term for official inspectors or commissaries, the origin of the local name is plain.