Revolving-Drum Toothed-Bar Churn: The Churn Turns Round a Fixed Toothed Bar

Clarke turned the churn itself and held the beater still. George B. Clarke of Leonardsville, New York, received US 8,373, dated 23 September 1851, for "Clarke's excelsior churn": a cylinder hung horizontally and revolving on fixed axles, with cleats inside, "either with or without projections," working between teeth on a stationary cross bar fixed to the axles a little off centre, to "break the circular motion of the milk and thereby cause it to be precipitated on the cylinder at the center." A stationary metal cylinder inside, fed warm or cold water through tubes in the hollow axles by a pump worked from the churn, tempers the milk; funnels in the axles let air in. This rung works out the speed limit, then prints the cleats, toothed bar and axle blocks, builds the drum on a frame, and makes butter.