or mix, rather they extrude clay bodies prior to shaping processes. Some can be fitted with a vacuum system that ensures the extruded clay bodies have no entrapped air. According to the 1913 edition of Webster's Dictionary, a clay pug mill typically consists of an upright shaft armed with projecting knives, which is caused to revolve in a hollow cylinder, tub, or vat, in which the clay body is placed. Pugmills that run intermittently are used in the kaolin mining industry to mix certain grades of kaolin clay with water. See also Concrete slump test References External links Pugmill mixing explanation Pug Mill page at potteries.org Pugmill Mixer Selection Guide Wedging, a way to manually remove air bubbles from clay Tools Industrial processes Ceramic engineering Pavement engineering Materials science