Though it would be easy to suggest many possible places of origin for these wares, such speculation can be of no real value without far more definite evidence than we possess at present. Still, it may serve some useful purpose in the future, if not at once, if we add one or two more records, however meagre, to the existing lists of Chinese potteries. The section of the _T´u shu_, which is devoted to _T´ao kung_ (the pottery industry), mentions the following factories as of some importance in the Ming dynasty. In the province of Honan, in addition to the well-known potteries of Chün Chou and Ju Chou, we read that there was a factory in the Ju-ning Fu at the village of Ts´ai [Chinese], which was intermittently active in the first half of the fifteenth century.[426] From another passage we learn that in the valleys of Ching[427] [Chinese] and the hills of Shu (or Szech´uan) there are black and yellow clays suitable for pottery; that the potters had their kilns in holes in the mountains; and that they used the yellow clay for the body of the ware and overlaid it with the black, making jars, drug pots, cauldrons, pots, dishes, bowls, sacrificial vessels, and the like. They also made one kind of ware which resembled that of Chün Chou. Specimens of modern pottery in the Field Museum, Chicago, include ornamental wares such as pomegranate-shaped water pots, etc., covered with an oily green glaze recalling some of the Sung types. The body is apparently dark coloured, and shows brown at the edges where the glaze is thin. This ware is made at Ch´êng-tu in Szech´uan. The geographical annals of the province of Shensi are quoted[428] with reference to potteries in the T´ung-chou Fu as follows: "The inhabitants of Lei-hsiang and Pai-shui[429] are good potters, and the porcelains (_tz´ŭ ch´i_) which they make are of surpassingly clever workmanship. These are what are commonly called _lei kung ch´i_ (vessels of the Lord of Thunder). Some say that the potteries of Hsiang only began to be active when the original wares had ceased to be made. The village of Lei-hsiang is east of Shên Hsien, and it is the place of the temple of the Hsiang family. The inhabitants of the place sometimes dig up castaway Hsiang wares. Their shape and style are archaic; the colour of the ware is green (_lü_), deep and dark, but brilliant. One kind has slight ornament in raised clay, but if the hand is passed over it, the surface feels smooth and without perceptible relief or indentation.[430] When compared with the Hsüan,[431] Ko and other wares, it may be said to surpass them." The description in the last part seems to apply to the older wares which preceded those made in the district at the time of writing.