A surgical apparatus includes an elongated shaft having a pair of relatively movable jaws at a distal end thereof. The system includes storage apparatus associated with each delivery bay and adapted to receive aggregate by gravity feeding from that delivery bay, wherein each storage apparatus includes one or more storage hoppers. In certain described examples, time values obtained in response to signals indicative of transaction initiation events are added to a data queue. The second input terminal of the second transfer gate is connected to the first output terminal.