Abstract: A lift has a base frame supported on a pair of screw jacks and a pair of support legs when a multi-stage mast on the lift is to be raised. The support legs are slide mounted in guides and each is downwardly biased away from a control switch on the base frame so that the switch is open unless the leg is loaded by the weight of the lift. A transport carriage is mounted to roll on sloped tracks on the base frame and is connected to the base frame by a hydraulic cylinder unit which functions when activated to pull the carriage downwardly into ground engagement to take the load of the lift from the jacks and support legs. A control circuit prevents the mast from being raised while the lift is supported on the carriage.