Surveying the Mason Dixon Line

The Mason-Dixon line, although drawn in 1763, ishad been almost completely surveyed by the pair,
still used today to describe the division betweenfinally settling the dispute. The line as originally
the northern and southern parts of the Unitedsurveyed by the pair was marked by stones
States.every mile and larger "crownstones" every five
The area was first surveyed by Charles Masonmiles. Though many today are missing or buried,
and Jeremiah Dixon to settle a property dispute.some are still visible.
Although the line would come to have historicalOver five decades later, the area would again be
importance years later, it was first drawn tothrown into controversy, although this time on a
settle a dispute between descendants of Georgenational scale. The same boundary delineated by
Calvert of Maryland and William Penn ofthe Mason-Dixon line became the main debate of
Pennsylvania over the boundary between the twothe Missouri Compromise of 1820. This
states. According to the charters originally grantedcompromise used that line as the boundary
to Calvert and Penn for establishing Maryland andbetween southern (slave) states and northern
Pennsylvania, respectively, the land between the(free) states, as Pennsylvania had officially
39th and 40th parallels belonged to both Marylandabolished slavery in 1781, while Maryland was still a
and Pennsylvania. As a result, the two sidesslave state. According to the compromise, the
argued over the boundary for several decades.states above the line would be free states, while
The biggest problem with this that underthose below the line could be slave states. The
Maryland's claim, Philadelphia would actually beline surveyed by Mason and Dixon was extended
within Maryland, not Pennsylvania, and both sideswest to the Mississippi River at this time. It also
wanted to lay claim to the town.forms parts of the boundaries of Delaware and
The compromise was finally drawn from 1763 toWest Virginia.
1765 by Charles Mason and Jeremiah Dixon, anIn history, the name "Mason-Dixon line" symbolizes
astronomer and a surveyor, both from England.much more than a compromise between two
The compromise set the boundary betweenstates on boundaries; it has become associated
southern Pennsylvania and northern Maryland atwith the struggle between slave and free states
15 miles south of Philadelphia, granting Philadelphiawhich would eventually be resolved only by the
to Pennsylvania. First, they precisely pinpointed theCivil War. Although the term Mason-Dixon line
area fifteen miles south of Philadelphia, erecting aoriginally referred to the boundary dispute
limestone benchmark at this point. Then, theycompromise, by the mid-nineteenth century it
began surveying west of this point, which wascame to symbolize to divide between slavery and
rugged land with many Native Americans living indiscrimination, in the south, and freedom, in the
the region. Although they set out to survey 233north. It can also be used to describe the
miles of land, but these hazards kept them fromindefinable cultural boundary between north and
completing this goal. In 1767, the Mason-Dixon linesouth.