Keywords: history of technology historyoftechnology mining smithsonian probably public domain probablypublicdomain blackandwhite monochrome outdoor black and white SI Neg. CCC-1859. Date: 1920....201 Mine Portal.No 201 Mine Portal 20 reg..From the Consolidation Coal Company collection, National Museum of American History...Credit: unknown (Smithsonian Institution) SI Neg. CCC-1859. Date: 1920....201 Mine Portal.No 201 Mine Portal 20 reg..From the Consolidation Coal Company collection, National Museum of American History...Credit: unknown (Smithsonian Institution) |