madrier, madrier

[Fr.) Military Engineering: IMG:content-0811.jpg:[graphic] 1. A thick, iron-plated plank, having a cavity to receive the mouth of a petard, which is applied to a gate or other obstacle to be blown down. 2. A beam laid in a ditch to support a wall; or in a mine or bomb-proof to support a side or roof. 3. A plank lined with tin and covered with earth to form roofs over certain portions of military works to afford protection against fires in lodgments, .