Blasting

the operation of breaking up ma es of stone or rock in situ by means of gunpowder or other explosive. In ordinary operations, holes are bored into the rock of from one to six inches in diameter, by means of a steel pointed drill, by striking it with hammers or allowing it to fall from a height. After the hole is bored to the requisite depth it is cleaned out, the explosive is introduced, the hole is tamped or filled up with broken stone, ri! or sand, and the charge exploded by means of a fuse or by electricity.