A cockermeg is an older style of timber support used in underground coal mining. It consists of a horizontal piece of timber held in place against the coal face by two diagonal props, preventing the face from collapsing onto the miners while they undercut the seam. This specific geometry provides lateral stability against the pressure of the unmined coal.
Heard on the job
Set a cockermeg against that fractured face before you start underholing.
Insider tip
The term originates from British coalfields and is rarely used outside historical contexts or traditional manual mining setups.