Abstract: Propelling mechanism for forwarding a carrier of a power and free conveyor from the delivery end of a first carrier supporting track onto a track section of an elevator and thence onto the receiving end of a second carrier supporting track. The elevator includes a carriage to which the track section is attached and which is movable longitudinally to permit the track section to be extended from the elevator into registry with either the first or second carrier supporting track. A propelling member, consisting of a pair of roller chains connected in spaced side-by-side relation, is equipped at one end with a carrier pusher, is connected at the other end to an endless output chain of a reversible drive mounted on the carriage, and is supported and guided by tracks which extend parallel to the track section from the entrance end thereof and into a storage path parallel to the path of the endless output chain.