Cutting off the admission of steam to the cylinder before the piston has completed its stroke. ... The admission of air for the purpose of opening the door is controlled by a valve operated by a foot pedal ; the fireman, pressing down on the pedal with his foot, opens the valve and admits ... This body contains a circular valve having a guide stem at the top and bottom, the valve seating against the valve cap.
|Title||:||Brotherhood of Locomotive Firemen's Magazine|