a vacuum cleaner includes a housing having a suction opening disposed between front and rear brushes for sucking dirt from a floor . a rag disposed behind the rear brush is rotatably driven about a transverse axis by the reciprocal action of the housing as the latter is displaced along the floor . a water supply keeps the rag moist . the rag is driven such that the floor - engaging portion is driven in a direction opposite the direction of housing travel . an auxiliary opening in the suction line sucks dirt from the rag at a location above the floor .