A single-track haulage system operated by a haulage engine with two drums, each with a separate rope. The engine is usually located at the out end of the system. The main rope is attached to the out end of the set of tubs, and the tail rope passes around a sheave in, and is then attached to, the rear end of the set. To draw the full set out, the main rope is wound in, the tail rope being allowed to run free. To draw the empty set in, the tail rope is wound in, the main rope being allowed to run free. The tail rope is equal to twice the length of the haulage road. The main-and-tail haulage is adopted when the gradient is irregular and the empty set will not run in by gravity.