A Three-Wire Method of Plumbing a Shaft
SOME years ago the writer had the opportunity to plumb a number of mine-shafts, each of which presented various conditions and difficulties. This afforded the chance to compare several methods of shaft plumbing in the light of ease and rapidity. This comparison led to the development of an adaption of the Weisbach, or approximate alignment, method, to three wires in a single shaft.
Applications, Canadian, Mine, Mines, Operation, Permits, plumb-bob, surveyor, triangle, Plumbing, Shafts, Underground