Pipe aqueduct across the valley of the Wissahickon for conveying water from the Roxborough to the Mount Airy Reservoir. designed by Fred[rick] Graff [Jr.], Chief Engineer, Water Department, June 10, 1868. Details of construction by John W. Murphey, contractor for erection. Duval & Hunter, Phila. [lithographers]. Bound in "Annual Report of the Chief Engineer of the Water Department of the City of Philadelphia. Presented to councils February 16, 1871."