Hercules Cement, Stockertown, PA, photograph by Pat Martin

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Bethlehem Steel, Bethlehem, PA, photograph by Don Durfee

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Big Bend Slate Quarry, Slatedale, PA, photograph by Pat Martin

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Click here to link to black/white photographs by Sanjeev Arora

Martin Guitar, Nazareth, PA, photograph by Susan Martin

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Mack Truck Museum, Hanover Township, PA, photograph by Susan Martin

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F.L. Smidth-Fuller Engineering, Allentown, PA, photograph by Larry Mishkar

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Coal mine in Lansford, PA, photograph by Larry Mishkar

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Eckley Miners Village, Eckley, PA, photograph by Larry Mishkar

Eckley Miners Village, photograph by Don Durfee

Eckley Miners Village, photograph by Don Durfee

Haines Mill, Cetronia, PA, photograph by Don Durfee

Phillipsburg Pump House boilers, photograph by Larry Mishkar

Northampton Street Bridge, Easton, PA, photograph by Don Durfee

Northampton Street Bridge, Easton, PA, photograph by Don Durfee