General view of the exterior of the locker and lunch room facilities (Building 55) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the…

General view of the exterior of the garage (Building 54) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast section of…

General view of the exterior of the warehouse facilities (Building 53) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast…

General view of the exterior of the main office and laboratory facilities (Building 51) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in…

General view of the exterior of the laboratory facilities (Building 51) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast…

General view of the carpenter shop (Building 57), power house (Building 43), and warehouse (Building 53) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the…

General view of the south side of the power house (Building 43) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast section of…

General view of the exterior of the laboratory facilities (Building 51) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast…

General view of the north side of the power house (Building 43) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast section of…

General view of the west side of the sulphuric acid contact plant (Building 41) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the…

General view of the east side of the sulphuric acid contact plant (Building 41) and adjacent railroad tracks at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the…

General view of the exterior of the Hypo Department facility (Building 37) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast…

Exterior view of the sodium tungstate manufacturing facility (Building 34) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast…

Exterior view of a section of the sodium sulfide and glaubersalt manufacturing facility (Building 33) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the…

Exterior view of the road and railroad track running between the copper oxide and aluminum manufacturing facilities at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located…

Exterior view of a section of the semi-works at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast section of Philadelphia,…

Exterior view of a section of the sodium sulfide crystals manufacturing facility (Building 30) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware…

Exterior view of a section of the sodium sulfide manufacturing facility (Building 26) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the…

Exterior view of a section of the aluminum-chloride department at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast section of…

Exterior view of the storeroom (Building 18) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast section of Philadelphia,…

Exterior view of the southeast corner of the aluminum plant at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast section of…

Exterior view of the west side of the aluminum plant at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast section of…

Exterior view of the copper oxide, bauxite silos, and bauxite grinding facilities (Building 5) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware…

Exterior view of the copper oxide and bauxite silos (Building 5) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast section of…

Exterior view of a section of the zinc chloride manufacturing facility (Building 4) at the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the…