A Report of The Current Mining Developments Committee Coal Division C.I.M; Roof Bolting
L. M. DWARKIN; F. DOXEY; J. C. JOHNSTON
AVITAL FACTOR in the success of any coal mining operation is the method of roof support employed. A coal seam in place has been described as the filling in a geological sandwich and the process of mining as the art of snatching the filling from the midst of the sandwich.
Bolts, bolts, coal mining, Dominion Steel ＆ Coal Corporation, rock, U.S. Bureau of Mines, Mine, Mines, Rock, Rocks, Roof bolting, steel, Steels