MASON-DIXON LINE

MASON-DIXON LINE is the southern boundary line of Pennsylvania, and thereby the northern boundary

line of Delaware, Maryland, and West Virginia, formerly part of Virginia. It is best known historically as the dividing line between slavery and free soil in the period of history before the Civil War, but to some extent it has remained the symbolic border line—political, cultural, and social—between North and South.

The present Mason and Dixon line was the final result of several highly involved colonial and state boundary disputes. The first dispute was between Maryland and Pennsylvania. The Maryland Charter of 1632 granted to the Calvert family lands lying north of the Potomac River and "under the fortieth degree of Northerly Latitude." Almost fifty years later (1681), Charles II issued a charter making William Penn proprietor of lands between latitudes 40° N and 43° N and running west from the Delaware River though five degrees in longitude. The terms of the two charters were inconsistent and contradictory. A full century of dispute with regard to the southern boundary of Pennsylvania was the result. Had all Pennsylvania claims been substantiated, Baltimore would have been included in Pennsylvania, and Maryland reduced to a narrow strip. Had all Maryland claims been established, Philadelphia would have been within Maryland.

In 1760, after years of conferences, appeals to the Privy Council, much correspondence, attempted occupation, forced removal of settlers, and temporary agreements, the Maryland and Pennsylvania proprietors reached an agreement to resolve the dispute. Under its terms, two English surveyors, Charles Mason and Jeremiah Dixon, surveyed the boundary line. In 1767, after four years' work, Mason and Dixon located the boundary line between Maryland and Pennsylvania at 39° 44' north latitude. The crown ratified the results in 1769.

In the meantime Virginia claimed most of what is now southwestern Pennsylvania. Both colonies tried to exercise jurisdiction in the area, which led to conflicts in 1774 and 1775. That dispute ended when joint commissioners of the two states agreed to extend the Mason and Dixon line westward, a settlement not completed until 1784. Historically the Mason-Dixon line embodies a Pennsylvania boundary triumph.

BIBLIOGRAPHY

Buck, Solon J., and Elizabeth H. Buck, The Planting of Civilization in Western Pennsylvania. Pittsburgh, Pa.: University of Pittsburgh Press, 1939.

Danson, Edwin. Drawing the Line: How Mason and Dixon Surveyed the Most Famous Border in America. New York: John Wiley, 2001.

Gray, Richard J. Writing the South: Ideas of an American Region. New York: Cambridge University Press, 1986.

Illick, Joseph E. Colonial Pennsylvania: A History. New York: Scribners, 1976.

Morrison, Charles. The Western Boundary of Maryland. Parson, W. Va.: McClain Print Co., 1976.

Alfred P.James/c. p.

See alsoBoundary Disputes Between States ; Maryland ; Pennsylvania ; Sectionalism ; South, the: The Antebellum South ; Surveying ; Virginia .

Mason‐Dixon Line. The Mason‐Dixon Line initially established the boundary between Pennsylvania and Maryland, resolving a lengthy dispute between the Penn and Calvert families, proprietors of the respective colonies. Both families claimed land that included Philadelphia, while Pennsylvania claimed the so‐called lower counties that make up present‐day Delaware. The dispute produced armed conflicts over tax collection and occasional uprisings against one proprietary regime or the other. Under a 1760 agreement, the two families accepted a proposal for a survey to be conducted by a pair of English astronomers and surveyors, Charles Mason and Jeremiah Dixon. The agreement required the use of a complex series of calculations incorporating the most advanced surveying methods of the day. Mason and Dixon conducted their survey between 1763 and 1767, encountering rugged terrain, political intrigues, and hostile Native Americans in the western country. Their final demarcation determined the Maryland‐Pennsylvania boundary at parallel 39°43′17.6∈ N. In 1769 the British crown ratified the line; in 1784 it was extended to settle the Pennsylvania and Virginia (now West Virginia) boundary. The novelist Thomas Pynchon offered a fictionalized account of the project in Mason and Dixon (1997).

In the Antebellum Era the Mason‐Dixon Line marked the division between the northern free‐soil and southern slave states. With the 1820 Missouri Compromise, Congress applied the term to a line extending from the Pennsylvania border, down the Ohio River to its Mississippi River outlet. Since the Ohio River flowed in a southwesterly direction, Congress established the line at 36°30′ west of the Mississippi. The Mason‐Dixon Line, thereby, divided the nation geographically over the slave issue. It later became embedded in popular usage as a convenient shorthand for demarcating the northern boundary of the South.
See also Colonial Era; Penn, William; Regionalism; Slavery: Development and Expansion of Slavery.

Bibliography

Judith St. George , Mason and Dixon's Line of Fire, 1991.

Nicholas Casner

Mason-Dixon Line boundary between Pennsylvania and Maryland (running between lat. 39°43′26.3′′N and lat. 39°43′17.6′′N), surveyed by the English team of Charles Mason, a mathematician and astronomer, and Jeremiah Dixon, a mathematician and land surveyor, between 1763 and 1767. The ambiguous description of the boundaries in the Maryland and Pennsylvania charters led to a protracted disagreement between the proprietors of the two colonies, the Penns of Pennsylvania and the Calverts of Maryland. The dispute was submitted to the English court of chancery in 1735. A compromise between two families in 1760 resulted in the appointment of Mason and Dixon. By 1767 the surveyors had run their line 244 mi (393 km) west from the Delaware border, every fifth milestone bearing the Penn and Calvert arms. The survey was completed to the western limit of Maryland in 1773; in 1779 the line was extended to mark the southern boundary of Pennsylvania with Virginia (present-day West Virginia). Before the Civil War the term "Mason-Dixon Line" popularly designated the boundary dividing the slave states from the free states, and it is still used to distinguish the South from the North.

Bibliography: See study by E. Danson (2001).

Mason-Dixon Line the boundary between Maryland and Pennsylvania, named after the British astronomers, Charles Mason and Jeremiah Dixon, who conducted the boundary survey in 1763-67. In the 1820 congressional debates over the Missouri Compromise, which determined the area where slavery would be allowed as the United States expanded, the term was first used to denote the line separating the slave states in the South from the free states in the North. Henceforth the name referred not only to the Maryland-Pennsylvania boundary but also to a line along the Ohio River from Pennsylvania to the Mississippi River, then along the east, north, and west boundaries of Missouri, and then west along the 36°30′ parallel.

Mason-Dixon Line (or Mason and Dixon Line) The boundary line between Pennsylvania and Maryland, which was laid out in 1763–67 by the English surveyors Charles Mason and Jeremiah Dixon. The name was later applied to the entire southern boundary of Pennsylvania, and in the years before the American Civil War it represented the division between the Northern states and the slave-owning states of the South.

Mason–Dixon Line in the US, the boundary between Maryland and Pennsylvania, taken as the northern limit of the slave-owning states before the abolition of slavery; it is named after Charles Mason (1730–87) and Jeremiah Dixon (1733–77), English astronomers, who defined most of the boundary between Pennsylvania and Maryland by survey in 1763–7.

Mason-Dixon Line Border of Pennsylvania with Maryland and West Virginia, USA. It is named after the men who surveyed it in the 1760s. It was regarded as the dividing line between slave and free states at the time of the Missouri Compromise (1820–21), and became the popular name for the boundary between North and South in the USA.

Ma·son–Dix·on line / ˈdiksən/ (also Ma·son-Dix·on Line) • n. (in the U.S.) the boundary between Maryland and Pennsylvania, taken as the northern limit of the slave-owning states before the abolition of slavery.