Search U.S. government technical reports digitized or harvested by TRAIL.
Hydraulic tunneling in St. Peter sandstone at Minneapolis, Minn.
Carbide insert bit drilling at the Cleveland-Cliffs Iron Co. mines, Ishpeming, Mich.
Tunnel construction by peripheral sawing at the Fort Randall Reservoir, Pickstown, S. Dak.
Ventilation-air heating plants of the Menominee Range
Investigation of Cuyuna iron-range manganese deposits, Crow Wing County, Minn. :progress report 1