Description of the Twenty
Illustrations of the Manufacture of Porcelain

By Tang Ying, Director of the Imperial Factory at Jingdechen,
in obedience to an Imperial edict... (1743)

18. Open and Closed Muffle Stoves

"White paste porcelain that has been previously fired in the furnace is first decorated by the artist with painting in colors. When it has been painted in colors it must be again fired to fix the colors. For this purpose two kinds of muff le stoves are used, one kind being open, the other closed.

"The open stove is used for the smaller pieces. This stove is similar to that used for cloisonné enamels on copper, and it has a door opening outward.

When the charcoal fire has been lighted inside, the porcelain is placed upon an iron wheel, which is supported upon an iron fork, by which the porcelain is passed into the stove, and the fireman holds in his other hand an iron hook, so that he may be able to turn the wheel around in the fire to equalize the action of the heat. When the colors appear clear and bright the firing is reckoned to have been sufficient.

For large pieces the closed stove is employed. This stove is three feet high and nearly two feet and three-quarters in diameter. A double wall to hold the charcoal fire, the wall being perforated below for the entrance of air, surrounds it. The porcelain is introduced into the interior of the stove, while the man holds a circular shield to protect him from the heat of the fire. The top of the stove is then closed by a flat cover of yellow clay and closely luted. The firing takes a period of about twenty-four hours.

The process of firing the monochrome yellow, green, and purplish brown porcelains is the same as the above."

This page is based on an original translation from Chinese by S.W. Bushell, 1899, of a text written on Imperial command in 1743 by Tang Ying, the celebrated superintendent of the porcelain manufacture in the province of Jiangxi. It is widely reprinted. The version most likely to be authentic is the version found in the official annals of the province of Jianxi, Book XCIII, folio 19-23. The first draft seems to have been written in 1735. The version above was added to a set of 'twenty illustrations of the manufacture of porcelain' in 1743. The actual illustrations have never been identified. The text as it appears here is illustrated with photos taken on location by Jan-Erik Nilsson in 1991 and 1992.