Three Versions of a Boundary:
Mason Dixon Lines-Past to Present

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American Philosophical Society Museum, Philadelphia, PA

Materials & Dimensions:
Ink and colored pencil drawing on Japanese kozo paper adhered to wall with reversible archival glue; each map 6 inches wide x 35 feet long.

Charles Mason and Jeremiah Dixon began their commissioned survey of the line that became the border between Pennsylvania and Maryland and Delaware in November 1763, and completed it in October 1767. The format of the maps in this installation is based on a map of the survey that was published as an engraving in 1768. The original edition was printed from two plates. The prints were cut apart and reassembled to make what we might now consider the first strip map. One of the original prints was in the exhibition Undaunted: 5 American Explorers in the American Philosophical Society Hall. This installation was designed to coincide with the historical exhibition.

The three hand-drawn strip maps adhered to the foyer wall were situated to take advantage of the elliptical curvature of the entrance foyer and of its balcony as a viewing platform. Binoculars were provided to allow visitors to examine the maps in detail from the balcony "cliff".

Scale of each map: 1 inch = 1 mile

Boundaries have great significance to exploration and observation: motivating it in the sense of what needs to be observed to find the line, which is itself imaginary and not physical, and what needs to be done physically to make it observable. In the case of the boundaries that Mason and Dixon surveyed, this required looking at the stars to find a line on the ground, cutting "vistos" through the wilderness to make a clearing to project the line, measuring the distance on the ground with chains and rods, and marking the mile intervals with wood posts and the five-mile intervals with stone posts. All this required traversing each part of the line at least twice, and doing so with a large team of men and a heavy burden of supplies and equipment.

The first (top) map is the original 1768 Mason Dixon line map enlarged. It shows the land in a flat plan. The landscape features were engraved in proportion as the mind imagines them rather than as they occupy the territory. However, the locations of the 5-mile markers on the line itself were correctly rendered to scale.

The second map is the same band of land as surveyed today, showing topography contours, woodlands, and waterways/swamps/lakes to scale. This map shows both the distance and the ruggedness of the line. Yet its bird's eye view remains in stark contrast to the difficulties of the ruggedness of the travel on the ground. This difference of how it felt to find and mark the Mason Dixon line and how the line was then recorded gives a crucial insight to the differences between the experience of exploration and the subsequent recording of explored territories. The abstraction of maps can never convey the exigencies required to make them possible.

The third map reveals the present congestion of the space with its network of highways, roads, and streets and the many municipalities that have developed. The mapped boundary line began as a matter of ownership and became a matter of conflict and political identity, later separating the slave states from the free states. One line has extrapolated to innumerable ones in an unending process. All this present development is in part the consequence of making a clearing, defining a boundary, starting a path in order to discover where you are.

The survey was stopped in 1767, not because it was complete, but due to another line: Mason and Dixon had arrived at the Great Warrior Path of the Native American Six Nations near Dunkard Creek. They were advised by their Mohawk guides that the Chiefs of the Six Nations could not guarantee their safety beyond that line.