Search U.S. government technical reports digitized or harvested by TRAIL.
The Bureau of Mines coal-sampling truck
Underground transportation of coal :Progress report 1
Underground transportation of coal :progress report [No.] 2
Multiple-shift mechanical mining in some bituminous-coal mines.
An analysis of the use of electricity at coal mines.
Two devices to prevent electric arcs with airdox operations in coal mines
Mechanical mining in some bituminous-coal mines.
A study of stray electric currents in airdox systems in coal mines
Safety aspects of controls and operations of belt conveyors in coal mines
Coal mine equipment forecast to 1985
Surface testing and evaluation of the conveyor belt service machine