CHINA
superiority in respect of delicacy of pâte and purity of colour thus rested with the Pai-ting. On the other hand, it is certain that technical processes were continually progressing through this long interval, and that the ware of the thirteenth century appreciably excelled that of the tenth in many important features. Chinese authors themselves state that the most beautiful pieces of northern Ting-yao were manufactured in the interval between 1111 and 1125; that is to say, just before political troubles compelled the transfer of the factory from Ting-chou to Nan-chang. It is reasonable to suppose that the potters did not leave their technical skill behind them at Ting-chou, and that their work in the south continued to improve as it had done in the north. But there is little to guide in this matter. Practical experience of the Ting-yao of the Sung dynasty leaves the student completely in the dark in respect of such fine distinctions as Pai-ting and Nan-ting.
It will be well to pass from the Ting-yao to the Ju-yao because the latter is said to have had its origin in technical defects of the former. The Tao-lu says that the glaze of the Ting-yao was often disfigured by fissures and other faults, due to imperfectly prepared materials or unskilled stoving. These blemishes proved so embarrassing and unavoidable that, in 1130 A.D., imperial orders were issued for the establishment of a special factory at Juchou, in the province of Kiang-su. Here the Ju-yao was produced. A Chinese writer, whose work was published at the close of the sixteenth century, says that the Chai and Ju porcelains, though the best of all, had ceased to exist in his time. The same writer's father, however, mentions that in his day specimens of Ju-yao were
32
