6 CASSIER'S CATALOGUE THEW SHOVELS FOR PITCH CONSTRUCTION Hydraulic mining methods for placer work frequently necessitate the construction of ditches under conditions involving excessive costs for labor and teams. Ordinary ex- cavating machinery cannot be employed, not being adapted for light work,… … Under the conditions shown in DITCH CONSTRUCTION IN ALASKA the cut, the shovel averaged over 150 cubic yards per shift. In surface excavation this can be doubled or tripled under favorable conditions. SHOVELS FOR ALL CLASSES OF MINING OPERATIONS EQUIPPED FOR STEAM, COMPRESSED AIR OR ELECTRICITY…
Engineering
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