Abstract: A double drum batch washing machine comprises an inner cylinder, an outer cylinder, an inner helical transfer screw with the inner cylinder and an outer helical transfer screw within the space between the inner and outer cylinders. The inner helical transfer screw has a pitch in one direction and the outer helical transfer screw has a pitch in the other direction so that the compartments formed by the transfer screws within the inner cylinder and the space between the inner and outer cylinders define areas of overlap on the surface of the inner cylinder. The areas of overlap have holes formed therein so that fluid interchange is established between each outer compartment and only the corresponding overlapping inner compartment. Laundry is placed in the inner compartments and wash water is placed in the outer compartments such that it communicates with the inner compartments and the laundry contained therein. Laundry is washed by oscillating the washing machine through a predetermined angular arc.