New Philadelphia, Illinois was the first town platted and legally registered by an African American in the United States. Founded by Frank McWorter, a former slave, in 1836, this town grew as a demographically integrated community through the late nineteenth century. New Philadelphia was platted on undeveloped prairie in a grid pattern with 42 acres of space, divided into 20 blocks, 144 lots, alleyways, and several streets (Figure 1). The town population reached a peak of approximately 160 people, 29 households, and merchant and crafts operations listed in the 1865 federal census. New Philadelphia was bypassed by a new railroad in 1869 and the population declined steadily thereafter. By 1885, the status of the community as a town was eliminated and large tracts of the land were put into agricultural use. Today, no structures from the town remain above ground, and the town site is covered by prairie grasses and agricultural fields.
The National Park System Landmarks Committee confirmed the national historic importance of the town site of New Philadelphia, on October 29, 2008. The Landmarks Committee voted unanimously to recommend the property for National Historic Landmark (NHL) status to the National Park System Advisory Board. In turn, the Advisory Board reviewed the nomination on December 3, 2008, and recommended its approval to the Secretary of the Interior, who holds final authority to make the designation. Listed among more than 83,000 historic properties on the National Register of Historic Places in 2005, New Philadelphia, upon final approval by the Secretary of the Interior, will join the elite group of approximately 2,500 historic sites deemed to be exceptionally significant to our country’s history. The historic town site qualifies for NHL status for its high degree of archaeological integrity and the potential it holds to provide scientific information of major importance (King 2008; Gaumer and Quimby 2006; U.S. Department of the Interior 1998, 1999). This nomination received official support from U.S. Senators Barack Obama and Richard Durbin; U.S. Representatives Ray LaHood and John Shimkus; Illinois Senators Deanna Demuzio, Emil Jones, Jr., and John Sullivan; and Illinois Representative Jil Tracy, among others. Upon final approval by the Secretary of the Interior later this year, the New Philadelphia town site will be formally designated as a National Historic Landmark with significant archaeological resources.
Federal and state census records, tax records, and deeds from the nineteenth century provide extensive data about New Philadelphia’s past residents. However, such historical documents do not provide a specific spatial map of household and merchant locations. Archaeological survey and excavations can map those locations in much greater detail to provide a richer data set for the social history of this community. The 1836 plat provides a plan for the town, including a grid pattern of streets, alleys, and lots, but the question remains as to whether this design was followed as the town developed. Indeed, nineteenth-century newspaper reports during the town’s existence indicated that town residents did not adhere to planned property lines in their building activities. Limited archaeological excavations at the town site, funded by the National Science Foundation’s program of Research Experiences for Undergraduates, have also uncovered early structures for which documentary evidence from deeds and other historical records provided no indications.
A number of archaeological survey and prospection methods have been employed previously at the New Philadelphia town site by collaborating researchers. These survey methods have included a pedestrian survey and surface collection of a large portion of the town site. Dr. Michael Hargrave, of the Construction Engineering Research Laboratory and U.S Army Engineer Research and Development Center in Champaign, Illinois, has also conducted 6.5 acres of surface-based geophysical surveys at the town site utilizing electric resistivity and magnetic gradient sensors (Hargrave 2006). Due to the large size of New Philadelphia as platted, it is not practical to attempt surface-based geophysical surveys of the entire town site.
The National Center for Preservation Technology and Training (NCPTT) awarded funding of $14,800 to test the usefulness of low-altitude aerial surveys employing high resolution thermal imaging at New Philadelphia. This method was employed at the town site in May 2008 for a new and specific purpose: determining whether this technology can detect the grid pattern and structural remains of an historic town site buried beneath 1-2 feet of agricultural fields and prairie grasses. If successful, this technique will provide an extremely useful resource for applications on numerous similar sites throughout the nation.
Dr. Tommy Hailey of Northwestern State University in Natchitoches, Louisiana, and Mr. Bryan Haley of the University of Mississippi, have pioneered the techniques used in combination in this survey, and they collected and processed the survey data utilizing a powered parachute ultralight aircraft and a high resolution thermal camera. The data sets were geo-referenced and integrated using spatial mapping programs, such as Geographic Information Systems software, and the creation of mosaic imaging representations. The survey results were also examined in relation to a geo-referenced version of the 1836 town plan and other comparative data. Dr. Christopher Fennell of the University of Illinois at Urbana-Champaign served as principal investigator and provided overall coordination of the project.
Additional information about the New Philadelphia Archaeology Project is available on the internet at http://www.anthro.uiuc.edu/faculty/cfennell/NP/ (Fennell 2008a). The following discussion of this survey project and its results is provided by Bryan Haley’s report entitled “An Investigation of New Philadelphia Using Thermal Infrared Remote Sensing,” available online at http://www.anthro.uiuc.edu/faculty/cfennell/NP/2008ReportMenu.html (Haley 2008).