Tub′bing.
（Mining.) Lining a shaft with casks or cylindrical caissons, to avoid the caving in of the may be of suitable shapes for molding beading, rabbeting, etc. The stuff may be secured on the castiron feed-table by cramps at intervals of 3 feet, and the cutter-block carriage is provided with two pressure-rollers to keep down the stuff when the cramps are not required, and is raised or lowered by a handle in connection with two side-screws. The feedmotion is self-acting.
