Search U.S. government technical reports digitized or harvested by TRAIL.
Coal-mine fatalities in the United States, 1922
Falls of roof and coal in bituminous coal-mines
Production of explosives in the United States :during the calendar year 1927
The National Safety Competition to assist in the reduction of mine and quarry accidents
The National safety competition of 1930
Production of explosives in the United States during the calendar year 1930
The National safety competition of 1931
Production of explosives in the United States :during the calendar year 1931
The National safety competition of 1932
The National safety competition of 1935
The national safety competition of 1936