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Shaft sinking by rotary drilling
Sampling deep ore deposits by rotary drilling and methods of surveying and controlling the direction of drill holes
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Published Year
1940-1949 (1)
1950-1959 (1)
Subject
Rotary drilling (2) *
Shaft sinking (1)
Author
Johnson, A. C. (1)
Platt, D. H. (1)
Trengove, Russell R. (1)
