Search U.S. government technical reports digitized or harvested by TRAIL.
Timbering along the robbing line :factors influencing falls of roof in coal mines
Stop, look and listen! :the roof is going to fall
How are men killed in mines by falls of roof and coal?
Area of unsupported roof in coal mines :conditions and factor[s] for consideration
What the superintendent of a coal mine might do to prevent injury from falls of roof
What the mine foreman can do to prevent injury from falls of roof in coal mines
Timber withdrawing and devices used for this purpose in some coal mines