. Chambers's encyclopedia; a dictionary of universal knowledge for the people. ows in a milky state,charged with the finely-divided materials, into acisteru, where it is kept stirred until it is sufH-ciently supplied with the solid materials, and thethickened milky liquid is then drawn off, in properproportions, into a vat to which the prepared clayis also passed. The mixture of the two is thenallowed to subside until the water is nearly clear,when it is drawn off; and the sediment is deprivedof its surplus moisture, either by evaporation, or, inthe Ijest works, by a pneumatic-exhausting appar
. Chambers's encyclopedia; a dictionary of universal knowledge for the people. ows in a milky state,charged with the finely-divided materials, into acisteru, where it is kept stirred until it is sufH-ciently supplied with the solid materials, and thethickened milky liquid is then drawn off, in properproportions, into a vat to which the prepared clayis also passed. The mixture of the two is thenallowed to subside until the water is nearly clear,when it is drawn off; and the sediment is deprivedof its surplus moisture, either by evaporation, or, inthe Ijest works, by a pneumatic-exhausting appar-atus, which does it very quickly. The compositionis then a fine plastic material of the consistency oftough dough, and is ready for the potters use. Inprejiaring the finer materials for porcelain, manyotlier operations are required, all, however, havingthe same object, Aiz., the extremely minute divisionof the substances used. The prepared clay is taken to the tliroicing-yiiaclihic, or jwtters lathe, which is represented infig. 16. This consists of a fixed table A, through. Fig. 16. which passes the axle B, and rises a little above itssurface, and having on its u]iper end a disc C,which revolves with it. The axle is put into rapidmotion by turning the fly-wheel D, either l)y handor machinery; and this causes a rapid revolution ofthe disc C, upon which is placed the soft mass ofclay to be moulded. At E is seen an upright, witha small sliding-bar regulated by a screw ; this is theguide for the jiotter to regulate the height of thevessel he is making. When the lump of clay iarevolving, the potter,with his hands or withproper tools, fashionsit into any shape hepleases; his manage-ment of this requiresconsiderable skill, asnearlj- every articlerecjuirjs a different con-figuration. But somearticles are formed inmoulds, the mouldsbeing made of plasterof Paris. This answerswell for fine porcelainintended to be very thin, the plaster-mould absorbs much ofthe moisture in the pa
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