llion and Incas Silver Mining panying engravings, almost unrecognizable as the offspring Company, Colorado, the tunnel having been at the time driv- of the original French machine. en 600 feet into the mountain. This drill cut horizontally The machines used in driving tunnels bore from three to… … Fig. 4 “M1 wenty-four men were constantly employed in repairing Fig. 2 represents a “ No. 1 Prospecting Drill,” so called he eight machines.” cause of its general use in testing the character and value of The Commission proceed to say, that,even admitting the mines and quarries. It consists of a…
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