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Front: "Don single jacking, Glengarry mine" MacDonald knight using a hammer and drilling steel to create holes in rock. From the USDA Forest Service website: "Single jacking involves an individual holding a drilling steel in one hand and hitting it with a hammer held in the other. The single jacks have 3- or 4-pound heads and 10-inch handles. The short handle helps you place blows accurately and resists breaking better than longer handles. Engineer's...
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Bob Enzenroth repairing and overhauling a jackhammer. All rock drills not working properly were sent to the machine shop to be cleaned, repaired and returned to the mine for service.
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Bob Enzenroth in the machine shop at the Gilman Mine repairing and overhauling a jackhammer.
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Emmet Flaherty preparing to pre-heat two blank pieces of hollow drill steel. In the background is an automatic oil-fired forge which will bring these blanks to an exact temperature for forging. From the hollow drill blanks, finished pieces of lugged steel are formed for use in rock drills.