The design is previously engraven on a copper plate, and laid on a stone to warm. The colour (which has oxide of cobalt for its basis) is mixed with a preparation of oils, to fetch out the impression; this mixture is smeared over the surface of the plate and again cleaned off, leaving the liquid in the engraving only. The paper used to take off the impression is made expressly for this purpose; it is damped, laid on the copper plate, and passed between two iron rollers, as in ordinary copper-plate printing. The design, being transferred to the paper, is laid immediately upon the ware, being rubbed on with a flannel. After remaining a short time, the ware is put into a tub of water, and the paper is separated from it by a sponge, leaving the design in the most perfect state.
The ware is then dried, and taken to the oven to be burned; during this operation, the oil which has been mixed with the colour in the printing is destroyed, and the oxide of cobalt more firmly attached to the ware; it is then glazed.