Cast.

Cast. An object formed by pouring molten or liquid material into a mould, in which the substance sets or hardens, assuming the form and outlines of the mould, is a cast, and is said to be made by casting. The process has a very wide application in the arts; its principal utilisation being in connection with the metallic industries. Casting on the large scale, specially in connection with iron and brass work, including statuary, is known as Founding, and will be treated under that head, though the products are still termed castings. So also the process of casting types is called typefounding. But when small objects in metal are dealt with, as in the jewelry trade, the process is known simply as casting. Plaster of Paris is an important medium for obtaining the first permanent casts of artistic sculptures and mouldings from the clay models of artists, as well as for preparing copies of sculptured works. In the same way the moulded ornaments used by plasterers are also prepared in plaster of Paris (see GYPSUM). Casts from plaster moulds are also made in wax for models of fruits, human masks, and other subjects reproduced in wax. Casting is further employed in glass manufacture, in which moulded and cast ornaments and forms are a feature precisely analogous to casting in other media. When the material employed in obtaining an impression from a mould is of doughy consistency requiring to be kneaded in the process, it is known as moulding, and that forms an important feature in the pottery manufacture.