1999 Conditions Assessment Survey of the Exterior Marble:
~~ Project Overview/Phase One

		University of Pennsylvania graduate student records measurements of exterior marble during six-week Conservation Field School in 1999.

The development of a conservation plan for the Second Bank of the United States will require several phases of research and investigation including archival documentation, condition survey and recording, laboratory and field analysis, and testing of proposed treatment interventions. Components of this research have been underway since 1986, however the current program of work has focused on a detailed survey of the marble masonry of the north portico and facade (the main entrance to the Second Bank from Chestnut Street), and the full west elevation. The survey was conducted from June 7 through July 16, 1999. A total of six graduate and post graduate interns from the Architectural Conservation Laboratory of the Graduate Program in Historic Preservation at the University of Pennsylvania conducted a complete investigation of both elevations with the use of movable scaffolding and 60' and 45' high lift cranes with extending booms.

Rather than recording all surfaces with rectified photographs to survey conditions, existing Historic American Buildings Survey (HABS) drawings from a 1939 survey were digitized. The dimensions of architectural features and joint lines were checked in the field and corrected or added as needed. Once the coursing and stone dimensions were finalized, the base drawings were used to record detailed conditions of the masonry. Only critical areas that displayed complex deterioration patterns were photographed during the survey.

Teams alternated between recording conditions in the field and digitizing the conditions in AutoCAD® over the new drawings. During the six-week field school all elevations of the portico including the columns, pediment, ceiling, flooring and stairs as well as the entire west elevation were surveyed and digitized. Two interns continued for a three-week period beyond the field school to double check and complete the survey drawings.

In addition to the field survey and subsequent drawings, a searchable database in Microsoft Access®, website, and report were created. For the database each stone on the drawings was assigned a number, and each condition was entered as a separate category in the database allowing the user to find all the conditions for any numbered stone, or to query and determine how many, or which stones have a particular condition. All conditions will eventually be imported into ArcView® to allow for greater diagnostic manipulation.

Several sources were consulted for specific information relating to the original use of the Pennsylvania Blue marble as well as the repair and conservation history of the building. Research was mostly conducted at the Independence National Historical Park (INHP) office and the libraries of the University of Pennsylvania, both located in Philadelphia. The majority of the information specific to the building came from the files of the Historical Architect at INHP which contain articles from U.S. and state Geological Surveys and student research relating to Pennsylvania quarries.

A complete set of printed documents from this project have been submitted to the National Park Service at INHP and the Architectural Conservation Laboratory at the University of Pennsylvania. All field notes, computer files, and correspondence have been deposited in the Archives at INHP.