Contents of Part IT. 
CORRELATION. 
Mining. 
Transporting. 
Hoisting. 
Sizing. 
CONCENTRATION. 
DRAINAGE. 
VENTILATION. 
THEORY OF ORE CONCENTRATION. 
Reduction. 
The Blake crusher. 
Rolls. 
Sizing. 
Kinds of screening surfaces. 
Sorting. 
Uses of jigs and tables. 
ECONOMY OF MINING OPERATIONS. 
Cost of drilling. 
Prospect drilling. 
Mine drilling. 
Cost of shafting and drifting. 
Cost of stoping. 
Cost of blasting. 
Cost of timbering. 
Cost of pumping. 
Cornish pump work. 
Steam pump work. 
Cost of extraction of ore. 
Cost of hoisting. 
Cost of concentrating. 
Wear of crusherjjaws. 
Wear of roll shells. 
Wear of elevator buckets. 
Wear of centrifugal pumps. 
Wear of screens. 
Wear of rubber belting. 
Summary. 
Suggested improvements. 
Mining. 
Hand picking. 
Hauling. 
Hoisting. 
Feeding. 
Concentrating. 
Pumping. 
Drilling. 
HISTORICAL SKETCH AND MINE DIRECTORY. 
APPENDIX. — USEFUL INFORMATION. 
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