Search U.S. government technical reports digitized or harvested by TRAIL.
Safety achievements of a Pennsylvania bituminous-coal mine and of a coal-mine superintendent
Mining statutes of the state of Pennsylvania(summarized)
Factors and conditions that aid in alinement of pillar extraction lines in coal mining
Explosions in Pennsylvania coal mines, 1870-1932
Water problem in the Pennsylvania anthracite mining region
Why men were killed at Pennsylvania anthracite mines in 1950
Mine subsidence--extent and cost of control in a selected area.
Microfilming maps of abandoned anthracite mines :mines in the Western middle anthracite field