( n. )
A slow rising of the floor of a gallery, occasioned by the pressure of incumbent strata upon the pillars or sides; a gradual movement of mining ground.
( n. )
A slow rising of the floor of a gallery, occasioned by the pressure of incumbent strata upon the pillars or sides; a gradual movement of mining ground.
Webster's Revised Unabridged English Dictionary. Пересмотренный полный словарь английского языка Webster. 2012