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)

"In the manufacture of the round ware each several piece
has to be repeated hundreds or thousands of times."
Photo © Jan-Erik Nilsson, 1992

5. Preparation of the Molds for the Round Ware

"In the manufacture of the round ware each several piece has to be repeated hundreds or thousands of times. Without molds it would be most difficult to make the pieces all exactly alike.

The molds must be made in accordance with the original design, but the size can not be so precisely measured; they must be larger than the model, otherwise the piece will come out smaller than the pattern.

The raw paste, which is expanded and loose in texture, becomes during the process of firing contracted and solidified to about seven or eight tenths of its original size, a result following from the natural laws of physics.

The proper proportionate size of the unbaked piece is fixed by the mold, and therefore the molders use the term 'prepare' instead of 'make'. Each piece must have several molds prepared, and the size and pattern of the contents when taken out of the kiln must be exactly alike.

A good practical knowledge of the length of firing required and of the natural properties of the paste is necessary before it is possible to estimate the exact amount of shrinkage, so as to fashion the molds of the proper form. In the whole district of Jingdezhen there are only three or four workmen reputed clever at this special handiwork."

Page credit and sources
This page is based on an English translation by S. W. Bushell, first published in 1899, of a Chinese text compiled under imperial command in 1743. The author was Tang Ying, the superintendent of imperial porcelain production in Jiangxi. The text has been widely reprinted in later literature. The version generally regarded as the most authoritative is preserved in the Provincial Annals of Jiangxi (Jiangxi tongzhi), Book 93, folios 19 to 23. An earlier draft appears to have been written around 1735. In 1743, the text was incorporated into a set described as the “Twenty Illustrations of the Manufacture of Porcelain,” compiled under imperial auspices. The original illustrations associated with this set have not been securely identified. The present page is edited to more modern language in 2025, and illustrated with photographs taken on site in Jingdezhen in 1991 and 1992, by Jan-Erik Nilsson