Abstract: A reversible plough has a double acting hydraulic ram connected between the headstock and the reversing spindle to reverse the plough frame from a left handed to a right handed ploughing position, and vice versa. Hydraulically operating mechanism is provided in the headstock both to switch the flow of hydraulic fluid from one to the other end of the double acting ram and to apply additional reversing torque to the spindle at the midway position. The mechanism comprises two hydraulic cylinders acting upon a fork pivotally mounted in the headstock and engaging with a roller spaced radially of the spindle. As the midway position is approached, the roller displaces the fork from a rest position whereupon the fork is rotated by the cylinders to drive the reversing spindle through the midway position. Internal fluid pathways in the two cylinders effect the change of fluid flow to the double acting ram.