A material dumping system is suspendable by a single hoist line. A first hoist line pulley is attached to a forward attachment element on a dumping container so that the line can be wrapped under the first pulley to support the container. The hoist line extends from under the first pulley to a second pulley attachable to the hoist's support structure where it is wrapped over the second pulley to extend therefrom to a rearward attachment element on the dumping container. A selectively actuated hoist line brake permits rotation of both pulleys during normal raising and lowering of the dumping container with the container in a horizontal attitude. However, when it is desired to dump the contents of the container, the hoist line brake is actuated to prevent rotation of the second pulley while permitting rotation of the first pulley. The hoist line is then extended to tilt the container forward for dumping purposes.