"Twenty Illustrations of the Manufacture of Porcelain"
Written on Imperial Command, by Tang Ying in 1735-43

"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."

This text was 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 and the most authentic version is to be 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 and 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. Original translation from Chinese by S.W. Bushell, 1899. The text is illustrated with photos taken on location by Jan-Erik Nilsson in 1991 and 1992.