Map depicting the facility and grounds of the Charles Lennig and Company chemical manufacturing plant in Bridesburg, a neighborhood located along the Delaware River in the Northeast section of Philadelphia, Pennsylvania. The map is color-coded to indicate when each building was erected between 1925 and 1936. Charles Lennig and Company operated as a subsidiary of the Rohm and Haas Company, an international chemical company headquartered in Philadelphia, from 1920 to 1947.