“May not the striking fact that there is a place corresponding to either name suggest that one of them was passed by Polo in going, the other in returning? and that, this being the only locality between Ch’êng-tu fu and Chu-chau where there was any deviation between the two journeys, his geographical ideas may have become somewhat confused, as might now happen to any one in like case and not provided with a map? Thus the traveller himself might have put into Ramusio’s text the name of _Thaigin_ instead of _Caichu_. From Kiai-chau he would probably cross the River at T’ungkwan, whilst in returning by way of Taiching-kwan he would pass through P’uchau-fu (or _vice versâ_). The question as to Caichu may still be settled, as it must be possible to ascertain where the Kin resided.”[2] [Mr. Rockhill writes (_Land of the Lamas_, p. 17): “One hundred and twenty _li_ south-south-west of the city is Kiai Chou, with the largest salt works in China.” Richthofen has estimated that about 150,000 tons of salt are produced annually from the marshes around it.—H. C.] NOTE 3.—The eight days’ journey through richly cultivated plains run up the basin of the Wei River, the most important agricultural region of North-West China, and the core of early Chinese History. The _löss_ is here more than ever predominant, its yellow tinge affecting the whole landscape, and even the atmosphere. Here, according to Baron v. Richthofen, originated the use of the word _hwang_ “yellow,” as the symbol of the Earth, whence the primeval emperors were styled _Hwang-ti_, “Lord of the Earth,” but properly “Lord of the _Löss_.” [The Rev. C. Holcombe (_l.c._ p. 66) writes: “From T’ung-kwan to Si-ngan fu, the road runs in a direction nearly due west, through a most lovely section of country, having a range of high hills upon the south, and the Wei River on the north. The road lies through one long orchard, and the walled towns and cities lie thickly along, for the most part at a little distance from the highway.” Mr. Rockhill says (_Land of the Lamas_, pp. 19–20): “The road between T’ung-kwan and Si-ngan fu, a distance of 110 miles, is a fine highway—for China—with a ditch on either side, rows of willow-trees here and there, and substantial stone bridges and culverts over the little streams which cross it. The basin of the Wei ho, in which this part of the province lies, has been for thousands of years one of the granaries of China. It was the colour of its loess-covered soil, called ‘yellow earth’ by the Chinese, that suggested the use of yellow as the colour sacred to imperial majesty. Wheat and sorghum are the principal crops, but we saw also numerous paddy fields where flocks of flamingoes were wading, and fruit-trees grew everywhere.”—H. C.]