horizontal. The operator then places the stack of mail against the feed member of the sorting machine, which then feeds the articles into the sorting machine, one at a time, to be sorted.
At the output of the sorter, the sorted articles are routed to the appropriate compartment for each of the sorted articles and stacked. The feeding and sorting of articles continues until one or more of the receiving compartments becomes sufficiently full of a stack of sorted mail. At this point, an operator will manually remove a stack of the sorted articles from the compartment and place the articles into a box for either later reprocessing through the sorting machine, transferring to another sorting machine for further sorting or transporting to a delivery person, such as aarticles from a cartridge having an openable door and a longitudinally slidable rear stack support paddle for supporting a rear of the stack, and queuing the stack for feeding to a flat article processing machine, further including:
a movable mechanical arm for placing the cartridge on and removing the cartridge from a receiving dock;
hold bar for supporting the front of the stack while the door is opened;
a cam for opening the door by means of relative movement between a cam on the receiving dock and a cam follower on the door as the cartridge is placed on the receiving dock and for closing the door when the cartridge is removed from the receiving dock;
a front finger for supporting the front of the stack during removal thereof from the cartridge;
a