Excavator At Work
Inga Spence
Excavation Of Indian Mound, 1850
Science Source
Coal Surface Mine
Inga Spence
Moving Logs
William H. Mullins
Loading Logs Onto A Truck
William H. Mullins
Harvest Mouse And Backhoe
Jean-Louis Klein & Marie-Luce Hubert
Engineer With Coal Sample
Inga Spence
Limestone Pit
Inga Spence
Contrast Between Using Land
Ikon Images
Heinrich Schliemann, German Archeologist #2
Science Source
Loading Logs Onto A Truck #3
William H. Mullins
Surface Coal Mine
Inga Spence
Surface Coal Mine #1
Inga Spence
Gold Mining Bucket Dredge
Theodore Clutter