I said, I., p. 225, that this town must be looked for on the river Hei-shui called Etsina by the Mongols, and would be situated on the river on the border of the Desert, at the top of a triangle, whose bases would be Suhchau and Kanchau.  My theory seems to be fully confirmed by Sir Aurel Stein, who writes: 

“Advantages of geographical position must at all times have invested this extensive riverine tract, limited as are its resources, with considerable importance for those, whether armed host or traders, who would make the long journey from the heart of Mongolia in the north to the Kansu oases.  It had been the same with the ancient Lou-lan delta, without which the Chinese could not have opened up the earliest and most direct route for the expansion of their trade and political influence into Central Asia.  The analogy thus presented could not fail to impress me even further when I proceeded to examine the ruins of Khara-khoto, the ‘Black Town’ which Colonel Kozloff, the distinguished Russian explorer, had been the first European to visit during his expedition of 1908-1909.  There remained no doubt for me then that it was identical with Marco Polo’s ’City of Etzina.’  Of this we are told in the great Venetian traveller’s narrative that it lay a twelve days’ ride from the city of Kan-chou, ’towards the north on the verge of the desert; it belongs to the Province of Tangut.’  All travellers bound for Kara-koram, the old capital of the Mongols, had here to lay in victuals for forty days in order to cross the great ’desert which extends forty days’ journey to the north, and on which you meet with no habitation nor baiting place.’

“The position thus indicated was found to correspond exactly to that of Khara-khoto, and the identification was completely borne out by the antiquarian evidence brought to light.  It soon showed me that though the town may have suffered considerably, as local tradition asserts, when Chingiz Khan with his Mongol army first invaded and conquered Kansu from this side about 1226 A.D., yet it continued to be inhabited down to Marco Polo’s time, and partially at least for more than a century later.  This was probably the case even longer with the agricultural settlement for which it had served as a local centre, and of which we traced extensive remains in the desert to the east and north-east.  But the town itself must have seen its most flourishing times under Tangut or Hsi-hsia rule from the beginning of the eleventh century down to the Mongol conquest.

“It was from this period, when Tibetan influence from the south seems to have made itself strongly felt throughout Kansu, that most of the Buddhist shrines and memorial Stupas dated, which filled a great portion of the ruined town and were conspicuous also outside it.  In one of the latter Colonel Kozloff had made his notable find of Buddhist texts and paintings.  But a systematic search of this and other ruins soon showed that the archaeological riches of the site