The potter’s craft, as we all know, had its origin in the dim ages of the past. Even the discovery of true porcelain must be dated so far back that we have no authentic record of the era of its origin. The literature of China ascribes the invention of true porcelain to some twenty-five hundred years before Christ, but we cannot be certain that the art of porcelain-making was known and practised until, perhaps, after the seventh century. While Chinese literature of the early periods abounds in references to porcelain, we have not a single authentic dated piece of the very early dynasties. It seems plausible to advance the theory that true porcelain was an invention or discovery of the Han dynasty (206 B.C.). The Japanese writer Okakura-Kakuzo has suggested that to the alchemists of the Han dynasty came accidentally the discovery of the wonderful porcelain glaze. The literature by Chinese authors of the T’ang dynasty is rich in references to porcelain. The poet Tu (803-852), for instance, says: The porcelain of the Ta-yi kilns is light yet strong, It rings with a low jade note and is famed throughout the city. The fine white bowls surpass hoar frost and snow. The white bowls of Hsing-chou in Chihli and the blue bowls of Yuen-chou in Che-kiang were highly esteemed and celebrated in song and story. Their resonance of tone was such that musicians were said to have utilized them. The Arabs and Chinese were conducting a flourishing trade during the eighth and ninth centuries. To Soleyman, one of the early Arabian traders who wrote an account of his journeyings, we owe the first mention of China in the literature of the world outside the empire. “In China,” said he, “they have a very fine clay which they manufacture vases from, as transparent as glass; water is seen through them.” Bushell (“Chinese Art,” vol. II) tells us that in the time of the Emperor Shi Tsung (954-959) of the brief Posterior Chou dynasty established at K’ai-fêng-fu prior to the Sung dynasty, an imperial rescript ordered porcelain “as blue as the sky, as clear as a mirror, as thin as paper and as resonant as a musical stone of jade.” All the porcelains of the times we have referred to seem long since to have disappeared and the only knowledge of them which we have to-day is through the literature of their contemporary writers. The Sung dynasty (960-1280), the Yuan dynasty (1280-1367), and the Ming dynasty (1368-1643) open up to us surer knowledge as specimens of the time are available to students. The porcelains of the Sung and Yuan dynasties may be classed together. The ceramic production (_yao_) made in the province of Honan in the town now called Ju-chou-fu--a Sung dynasty porcelain therefore designated as _Ju-Yao_--stands famous for the qualities of its blues, which Chinese poets assure us rival the blue blossoms of the _Vitex incisa_, the Chinese “Sky Blue Flower.”