Search U.S. government technical reports digitized or harvested by TRAIL.

Keyword Search

Sinking large-diameter drill holes, Lake Superior district underground iron mines

Support of ground, iron-ore mines, Lake Superior district

Published Year

• 1940-1949 (2)

Subject

• Iron mines and mining--Lake States (2) *
• Ground control (Mining)--Lake States (1)
• Shaft sinking (1)

Author

• Cash, Frank E. (2) *
• Johnson, Ernest W. (1)
• Petersen, Max S. (1)

• About TRAIL
• FAQ
• Join TRAIL
• Contact Us

Search developed and maintained by the University of Washington Libraries
Copyright 2010