A framework of timbers and plank backing for a shaft lining, to prevent caving, percolation of water, etc.
Cribbing time meant playing the card game cribbage, usually in the lunchroom when you should have been working. The lunch box became known as a crib box and lunch was refereed to as having your crib. The term also applied to the close setting of timbers usually in porous ground to stop leaching.
(1) timber framing to retain the walls and ceiling of an adit opening or drift, and prevent loose materials from falling, (2) a method of timbering in underground mining used primarily to rectify the removal of too great a percentage of the rock on the advance, and has the effect of replacing part of the rock.