the Wa, who occupy a tract on the north-eastern frontier, stretching for about a hundred miles along the Salween and some fifty miles in breadth. The Wa country is "a series of mountain ranges running north and south and shelving rapidly down to narrow valleys from two to five thousand feet deep. The villages are all on the slopes." Every village is surrounded by a rampart of earth, six to eight feet high and as many thick; round this is cut a deep
Fig. 55. Yang-sek women from the Shan Hills.
ditch. The only entrance is through a long tunnel. Inside the rampart, from 100 to 300 houses raised on piles, are built without order or design. Outside the village is a line of human skulls mounted on posts; for the best known characteristic of the Wa is the practice of head-hunting. Heads are collected as a protection against evil spirits, the idea being that the ghost of the owner of the head will haunt the place and keep off intruders. The Wa never raid outside their own country. To this may be attributed the
