pug mill

Century Dictionary and Cyclopedia

1. n. A machine for mixing and tempering clay. A common form consists of a hollow iron cylinder, generally set upright, with a revolving shaft in the line of its axis, carrying several knives arranged in a spiral manner round the shaft, with their edges somewhat depressed. The clay is thrown in at the top of the cylinder, cut and kneaded by the knives in its downward progress, and finally forced out through a hole in the bottom of the cylinder.

GNU Webster's 1913

1. n. a kind of mill for grinding and mixing clay, either for brickmaking or the fine arts; a clay mill. It consists essentially of an upright shaft armed with projecting knives, which is caused to revolve in a hollow cylinder, tub, or vat, in which the clay is placed.