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Scientific American, Vol. 37, No. 21 (1877) (1877)
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y sup- vantages attending the use of the latter underground. In plied as fast as it is required. sevenmonths. The rock is gneiss and quartz, and the ma- The principal point in the construction of the Rand drill so confined a space, where there is no exit for the exhaust chinery employed isthe Rand… … © 1877 SCIENTIFIC AMERICAN, INCInternet Archive · Public domain (published before 1931). Free to use for anything.
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