Page:A tour through the northern counties of England, and the borders of Scotland - Volume I.djvu/60

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facture. The works, conveniently situated, close to the Severn, which flows by the city, are remarkable for their neatness and convenience; and display the whole process of making porcelain, from grinding the various articles to compose the clay used for the purpose, to packing the finished pieces for the market. Interesting as this manufactory is, you will excuse me forgiving you its detail:—The mixture above-mentioned consists of fifteen articles, the chief of which are, a white granite, from Cornwall, and a steatite or soap-stone, from Penzance in the same county, the whole quarry of which belongs to Mr. Flight, who employs his own men there. These articles being first ground separately are afterwards mixed, and then calcined; the product of this process is a quantity of small blue and white lumps, which being thrown into a mill, and ground with soft water, a liquid of the consistence of thick cream is produced, perfectly white. This is passed through a lawn sieve, and then poured into vats, heated by outside flues in order to consolidate; the degree of heat applied to them being kept under the boiling temperature. The water gradually evaporating by these means from the contents of the vats, an hard clay remains in the room of the liquid, which is brought into a stone apartment to be tempered, that is, wetted with water, beaten with