Abstract: A drum defining a center axis is journalled from a support for rotation about its center axis through the utilization of resilient means permitting the axis and drum to gyrate about a center position of the axis responsive to dynamic imbalance of the drum during rotation thereof. The drum includes a plurality of circumferentially spaced liquid-passing openings and a plurality of liquid receptacles are mounted from the drum for receiving liquid therein from the openings. The receptacles are mounted from the drum for shifting between liquid retaining positions and liquid dumping positions and stationary receptacle position shifting structure is mounted from the support and the receptacles are mounted on the drum for normal disposition in either the liquid receiving positions or the liquid dumping positions.