Читать книгу How to make pottery онлайн

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Pottery clay differs from modelling clay in that it has more stiffening, so to speak. It is not so plastic, but, on the other hand, it will stand the heat of the kiln, which the other will not. The addition of whiting or felspar to modelling clay will give the needed stiffness. A pottery clay suitable for the work one can produce in one’s kiln must be so arranged as to harden at the degree of heat at which the kiln fires. Practically, we shall have little to do with any but the blue or ball clay and fire-clay. These are the best for pottery which is to be beautiful as well as useful. It is possible, of course, to use the flower-pot clay, and, perhaps, if one can easily obtain this clay, and is near enough to a pottery where the red ware is fired—so that one’s pieces can conveniently be sent there—it might be wiser to use it than to buy finer clays that come from a great distance, and then be obliged to send one’s pottery to a far-away kiln for firing.

The flower-pot ware is not strong, however, and fine glazes cannot be used upon it, so that, if possible, clay that will fire at a greater heat should be chosen. A mixture of fire-clay and ball or blue clay will give good results, and the pieces made with it may be sent to the nearest art pottery or to a kiln where stoneware is fired. Having once found a good clay, potters rarely change. In fact, this feeling is so strong with some that it amounts almost to a superstition. A potter who has obtained a clay that is satisfactory in a certain State will always send to the same State and bed for that clay, no matter how far he may be from it, nor how nearly the clay in his own State may come to the analysis of that which he has used.