NOTE 1.—The mountains that bound the splendid plain of Ch’êng-tu fu on the west rise rapidly to a height of 12,000 feet and upwards. Just at the skirt of this mountain region, where the great road to Lhása enters it, lies the large and bustling city of Yachaufu, forming the key of the hill country, and the great entrepôt of trade between Sze-ch’wan on the one side, and Tibet and Western Yunnan on the other. The present political boundary between China Proper and Tibet is to the west of Bathang and the Kin-sha Kiang, but till the beginning of last century it lay much further east, near _Ta-t’sien-lu_, or, as the Tibetans appear to call it, _Tartsédo_ or _Tachindo_, which a Chinese Itinerary given by Ritter makes to be 920 _li_, or 11 marches from Ch’êng-tu fu. In Marco’s time we must suppose that Tibet was considered to extend several marches further east still, or to the vicinity of Yachau.[1] Mr. Cooper’s Journal describes the country entered _on the 5th march_ from Ch’êng-tu as very mountainous, many of the neighbouring peaks being capped with snow. And he describes the people as speaking a language mixed with Tibetan for some distance before reaching Ta-t’sien-lu. Baron Richthofen also who, as we shall see, has thrown an entirely new light upon this part of Marco’s itinerary, was exactly five days in travelling through a rich and populous country, from Ch’êng-tu to Yachau. [Captain Gill left Ch’êng-tu on the 10th July, 1877, and reached Ya-chau on the 14th, a distance of 75 miles.—H. C.] (_Ritter_, IV. 190 _seqq._; _Cooper_, pp. 164–173; _Richthofen_ in _Verhandl. Ges. f. Erdk. zu Berlin_, 1874, p. 35.)