Topical Subjects
- Coal preparation plants--West Virginia.1
- Coal trade--Accidents.1
- Coal trade--Quality control.1
- Coal--Testing.1
- Coal--Transportation--Pennsylvania.1
- Coal--Transportation--West Virginia--Owings.1
- Coal--Transportation--West Virginia.1
- Coal-mining machinery--Ohio--Georgetown.1
- Conveying machinery.1
- Core drilling.1
- Grazing.1
- Industrial films.1
- Loading and unloading.1
- Machine shops.1
- Mine railroads.1
- Roof trusses.1
- Showers (Plumbing fixtures)1
- Smelting--West Virginia--Wheeling.1
- Steam locomotives--Pennsylvania--Somerset.1
- Steam locomotives--Pennsylvania.1