Star Gazers' Stone
Encyclopedia
Star Gazers' Stone located on Star Gazers' Farm near Embreeville, Pennsylvania
, USA
, marks the site of a temporary observatory established in January 1764 by Charles Mason
and Jeremiah Dixon
which they used in their survey of the Mason-Dixon line
. The stone was placed by Mason and Dixon about 700 feet (213 m) north of the Harlan House, which was used as a base of operations by Mason and Dixon through the four-and-a-half-year-long survey. Selected to be about 31 miles (50 km) west of the then southernmost point in Philadelphia, the observatory was used to determine the precise latitude of its location. The latitude of the Maryland
-Pennsylvania
border was then set to be 15 miles (24.1 km) south of the point in Philadelphia. The farm, including the house and stone, were listed on the National Register of Historic Places
on May 9, 1985.
Built c. 1724 near the forks of the Brandywine, the Harlan House was enlarged c.1758, and is likely the first house built in Newlin Township. The Harlan family lived in the house until 1956, and carefully preserved the location of the stone through the generations.
, was fought between Pennsylvania and Maryland. In 1760 the Crown intervened, defining the border as the line of latitude 15 miles (24.1 km) south of the southernmost house in Philadelphia. The proprietors of the colonies, the Penns and Calverts, then commissioned Mason and Dixon to survey
the newly established boundary.
Mason and Dixon used the finest instruments of their day in the survey, including a type of telescope, the zenith sector
built by John Bird
, used for measuring latitude and an "equal altitude and transit
" instrument for sighting survey lines, as well as a less accurate quadrant
for faster rough estimates of latitude, and a chronometer
built by John Harrison
, used for measuring longitude. Though Harrison's chronometers later became the standard instrument for measuring longitude, the surveyors' job was mainly to measure latitude, and Mason preferred the method of lunar distance
of measuring longitude to the new method.
On December 9, 1763 soon after arriving in Philadelphia, the surveyors received their instructions from the joint border commission:
The first instruction was completed by January 6, 1764 by constructing an observatory near the Huddle-Plumstead House on Cedar Street (now named South Street
) in Philadelphia, and measuring the angle of the zenith of eight stars. Rather than measure 15 miles (24.1 km) directly south of Philadelphia to start the survey, a westward move was needed to avoid crossing the wide Delaware River twice, and to avoid beginning the survey of the Pennsylvania-Maryland border in New Jersey.
The surveyors fulfilled the second instruction by January 13, as recorded in their journal:
The new site of the observatory was near marks that had been made by surveyors from New Jersey in 1730 and 1736.
By February 28 Mason and Dixon had determined the latitude at Star Gazers' Stone by observing the eight stars. After making adjustments for the distance their observatory was south of Philadelphia, Mason and Dixon measure 15 miles (24.1 km) south to a point in Delaware by April 21. In the first mile measuring south from their observatory they crossed Brandywine Creek three times. They moved the observatory to this point where they measured the latitude again and remeasured back to the Star Gazers' Stone. In May and June they again measured the latitude at Star Gazers' Stone. The southern point was named the "Post mark'd west" and the Maryland-Pennsylvania border was, after a delay, measured straight west from there.
Mason and Dixon returned to the house many times during the four and one-half years of the survey, often spending the winters there. On January 1, 1767, Mason recorded a temperature of minus 22 degrees Fahrenheit
at the farm. They returned to the observatory when they started the new task of measuring the distance of a degree of latitude in miles. They were reputed to be heavy drinkers, and local lore says that a nearby tributary of the Brandywine, Punch Run Creek, was named to commemorate their drinking. At the end of the survey, the Harlan house was one of the last places they visited before returning to Britain via Philadelphia.
who were born in Durham
, England
and immigrated to Pennsylvania about 1687 from County Down
, Ireland
. Michael's son George Harlan built the house in the forks of the Brandywine c.1724. In that year the Free Society of Traders sold 7000 acres (28.3 km²) to Nathaniel Newlin
, which became Newlin Township in Chester County
. Newlin immediately sold some of the land, including 169 acre (0.68391934 km²) in the forks of Brandywine Creek sold to George Harlan. A son, Joel, was born to George and Mary Harlan in 1724 in Newlin Township, presumably in their new house. The house was probably the first in the township. Tax assessments in the township were first made in 1739, and until 1760, Joel's older brother John Harlan paid the taxes on the house and farm. Sometime between 1758 and 1760 Joel returned to Newlin Township after living in other locations in Chester County, took ownership of the farm and built an addition to the house. Both John's and Joel's families apparently lived in the same house, but Mason and Dixon's Journal always refers to the "John Harland farm" or simply the "Harland farm." John Harlan died by drowning in the Brandywine in 1768.
The original house is two stories measuring 25 feet (7.6 m) by 16 feet (4.9 m), constructed of stone. The c.1758 addition was also constructed of stone and measures 25 feet (7.6 m) by 13 feet (4 m). A small frame addition was built in the nineteenth century.
The Harlan family lived on site until they sold the property in 1956. In 1908 the Chester County Historical Society dug up the Star Gazers' Stone, set it in concrete, built a low stone wall around it, and placed a plaque on the new wall. At the dedication, Henry K. Harlan said that each generation of the family was taught that the Star Gazers' Stone had an important place in American history and that they should not move the stone. Chester County now owns the stone.
Joshua Harlan, son of the immigrant George Harlan, built a log cabin known as the Harlan Log House
about 1715, about 12 miles (19.3 km) south in Kennett Township which is also listed on the National Register of Historic Places.
Embreeville, Pennsylvania
Embreeville is an historical unincorporated community, little more than a rural stretch of road with a few businesses and homes, mostly in Newlin Township, Chester County, Pennsylvania and partially in West Bradford Township, Chester County, Pennsylvania, inside a bend of Brandywine Creek. It is...
, USA
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, marks the site of a temporary observatory established in January 1764 by Charles Mason
Charles Mason
Charles Mason was an English astronomer who made significant contributions to 18th-century science and American history, particularly through his involvement with the survey of the Mason-Dixon line, which came to mark the division between the northern and southern United States...
and Jeremiah Dixon
Jeremiah Dixon
Jeremiah Dixon was an English surveyor and astronomer who is perhaps best known for his work with Charles Mason, from 1763 to 1767, in determining what was later called the Mason-Dixon line....
which they used in their survey of the Mason-Dixon line
Mason-Dixon line
The Mason–Dixon Line was surveyed between 1763 and 1767 by Charles Mason and Jeremiah Dixon in the resolution of a border dispute between British colonies in Colonial America. It forms a demarcation line among four U.S. states, forming part of the borders of Pennsylvania, Maryland, Delaware, and...
. The stone was placed by Mason and Dixon about 700 feet (213 m) north of the Harlan House, which was used as a base of operations by Mason and Dixon through the four-and-a-half-year-long survey. Selected to be about 31 miles (50 km) west of the then southernmost point in Philadelphia, the observatory was used to determine the precise latitude of its location. The latitude of the Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
-Pennsylvania
Pennsylvania
The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...
border was then set to be 15 miles (24.1 km) south of the point in Philadelphia. The farm, including the house and stone, were listed on the National Register of Historic Places
National Register of Historic Places
The National Register of Historic Places is the United States government's official list of districts, sites, buildings, structures, and objects deemed worthy of preservation...
on May 9, 1985.
Built c. 1724 near the forks of the Brandywine, the Harlan House was enlarged c.1758, and is likely the first house built in Newlin Township. The Harlan family lived in the house until 1956, and carefully preserved the location of the stone through the generations.
The observatory
Mason and Dixon's survey was the final step in the resolution of a border dispute between Pennsylvania and Maryland that lasted over 80 years. From 1730-1738 a violent border conflict, known as Cresap's WarCresap's War
Cresap's War was a border conflict between Pennsylvania and Maryland, fought in the 1730s...
, was fought between Pennsylvania and Maryland. In 1760 the Crown intervened, defining the border as the line of latitude 15 miles (24.1 km) south of the southernmost house in Philadelphia. The proprietors of the colonies, the Penns and Calverts, then commissioned Mason and Dixon to survey
Surveying
See Also: Public Land Survey SystemSurveying or land surveying is the technique, profession, and science of accurately determining the terrestrial or three-dimensional position of points and the distances and angles between them...
the newly established boundary.
Mason and Dixon used the finest instruments of their day in the survey, including a type of telescope, the zenith sector
Zenith telescope
A zenith telescope is a type of telescope that is designed to point straight up at or near the zenith. They are used for precision measurement of star positions, to simplify telescope construction, or both....
built by John Bird
John Bird (astronomer)
John Bird , the great mathematical instrument maker, was born at Bishop Auckland. He worked in London for Jeremiah Sisson, and by 1745 he had his own business in the Strand. Bird was commissioned to make a brass quadrant 8 feet across for the Royal Observatory at Greenwich, where it is still...
, used for measuring latitude and an "equal altitude and transit
Theodolite
A theodolite is a precision instrument for measuring angles in the horizontal and vertical planes. Theodolites are mainly used for surveying applications, and have been adapted for specialized purposes in fields like metrology and rocket launch technology...
" instrument for sighting survey lines, as well as a less accurate quadrant
Quadrant (instrument)
A quadrant is an instrument that is used to measure angles up to 90°. It was originally proposed by Ptolemy as a better kind of astrolabe. Several different variations of the instrument were later produced by medieval Muslim astronomers.-Types of quadrants:...
for faster rough estimates of latitude, and a chronometer
Chronometer
Chronometer may refer to:* Chronometer watch, a watch tested and certified to meet certain precision standards* Hydrochronometer, a water clock* Marine chronometer, a timekeeper used for celestial navigation...
built by John Harrison
John Harrison
John Harrison was a self-educated English clockmaker. He invented the marine chronometer, a long-sought device in solving the problem of establishing the East-West position or longitude of a ship at sea, thus revolutionising and extending the possibility of safe long distance sea travel in the Age...
, used for measuring longitude. Though Harrison's chronometers later became the standard instrument for measuring longitude, the surveyors' job was mainly to measure latitude, and Mason preferred the method of lunar distance
Lunar distance (navigation)
In celestial navigation, lunar distance is the angle between the Moon and another celestial body. A navigator can use a lunar distance and a nautical almanac to calculate Greenwich time...
of measuring longitude to the new method.
On December 9, 1763 soon after arriving in Philadelphia, the surveyors received their instructions from the joint border commission:
The first instruction was completed by January 6, 1764 by constructing an observatory near the Huddle-Plumstead House on Cedar Street (now named South Street
South Street (Philadelphia)
South Street is an east-west street forming the southern border of the Center City neighborhood of Philadelphia, Pennsylvania and the northern border for the neighborhoods of South Philadelphia. The stretch of South Street between Front Street and Seventh Street is known for its "bohemian"...
) in Philadelphia, and measuring the angle of the zenith of eight stars. Rather than measure 15 miles (24.1 km) directly south of Philadelphia to start the survey, a westward move was needed to avoid crossing the wide Delaware River twice, and to avoid beginning the survey of the Pennsylvania-Maryland border in New Jersey.
The surveyors fulfilled the second instruction by January 13, as recorded in their journal:
The new site of the observatory was near marks that had been made by surveyors from New Jersey in 1730 and 1736.
By February 28 Mason and Dixon had determined the latitude at Star Gazers' Stone by observing the eight stars. After making adjustments for the distance their observatory was south of Philadelphia, Mason and Dixon measure 15 miles (24.1 km) south to a point in Delaware by April 21. In the first mile measuring south from their observatory they crossed Brandywine Creek three times. They moved the observatory to this point where they measured the latitude again and remeasured back to the Star Gazers' Stone. In May and June they again measured the latitude at Star Gazers' Stone. The southern point was named the "Post mark'd west" and the Maryland-Pennsylvania border was, after a delay, measured straight west from there.
Mason and Dixon returned to the house many times during the four and one-half years of the survey, often spending the winters there. On January 1, 1767, Mason recorded a temperature of minus 22 degrees Fahrenheit
Fahrenheit
Fahrenheit is the temperature scale proposed in 1724 by, and named after, the German physicist Daniel Gabriel Fahrenheit . Within this scale, the freezing of water into ice is defined at 32 degrees, while the boiling point of water is defined to be 212 degrees...
at the farm. They returned to the observatory when they started the new task of measuring the distance of a degree of latitude in miles. They were reputed to be heavy drinkers, and local lore says that a nearby tributary of the Brandywine, Punch Run Creek, was named to commemorate their drinking. At the end of the survey, the Harlan house was one of the last places they visited before returning to Britain via Philadelphia.
The Harlan house and farm
Brothers George and Michael Harlan were QuakersReligious Society of Friends
The Religious Society of Friends, or Friends Church, is a Christian movement which stresses the doctrine of the priesthood of all believers. Members are known as Friends, or popularly as Quakers. It is made of independent organisations, which have split from one another due to doctrinal differences...
who were born in Durham
Durham
Durham is a city in north east England. It is within the County Durham local government district, and is the county town of the larger ceremonial county...
, England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
and immigrated to Pennsylvania about 1687 from County Down
County Down
-Cities:*Belfast *Newry -Large towns:*Dundonald*Newtownards*Bangor-Medium towns:...
, Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
. Michael's son George Harlan built the house in the forks of the Brandywine c.1724. In that year the Free Society of Traders sold 7000 acres (28.3 km²) to Nathaniel Newlin
Newlin Mill Complex
The Newlin Mill Complex, a water powered gristmill on the west branch of Chester Creek near Concordville, Pennsylvania, USA, was built in 1704 by Nathaniel and Mary Newlin and operated commercially until 1941. During its three centuries of operation, the mill has been known as the Lower Mill, the...
, which became Newlin Township in Chester County
Chester County, Pennsylvania
-State parks:*French Creek State Park*Marsh Creek State Park*White Clay Creek Preserve-Demographics:As of the 2010 census, the county was 85.5% White, 6.1% Black or African American, 0.2% Native American or Alaskan Native, 3.9% Asian, 0.0% Native Hawaiian, 1.8% were two or more races, and 2.4% were...
. Newlin immediately sold some of the land, including 169 acre (0.68391934 km²) in the forks of Brandywine Creek sold to George Harlan. A son, Joel, was born to George and Mary Harlan in 1724 in Newlin Township, presumably in their new house. The house was probably the first in the township. Tax assessments in the township were first made in 1739, and until 1760, Joel's older brother John Harlan paid the taxes on the house and farm. Sometime between 1758 and 1760 Joel returned to Newlin Township after living in other locations in Chester County, took ownership of the farm and built an addition to the house. Both John's and Joel's families apparently lived in the same house, but Mason and Dixon's Journal always refers to the "John Harland farm" or simply the "Harland farm." John Harlan died by drowning in the Brandywine in 1768.
The original house is two stories measuring 25 feet (7.6 m) by 16 feet (4.9 m), constructed of stone. The c.1758 addition was also constructed of stone and measures 25 feet (7.6 m) by 13 feet (4 m). A small frame addition was built in the nineteenth century.
The Harlan family lived on site until they sold the property in 1956. In 1908 the Chester County Historical Society dug up the Star Gazers' Stone, set it in concrete, built a low stone wall around it, and placed a plaque on the new wall. At the dedication, Henry K. Harlan said that each generation of the family was taught that the Star Gazers' Stone had an important place in American history and that they should not move the stone. Chester County now owns the stone.
Joshua Harlan, son of the immigrant George Harlan, built a log cabin known as the Harlan Log House
Harlan Log House
The Harlan Log House, built about 1715 by Joshua Harlan, is a well preserved example of an English-style log cabin, in Kennett Township, Chester County, Pennsylvania, United States about a half mile west of the hamlet of Fairville. Joshua Harlan was the son of George Harlan, who arrived in...
about 1715, about 12 miles (19.3 km) south in Kennett Township which is also listed on the National Register of Historic Places.
Sources
p. 158- Roby, Thomas C. (1984), National Register of Historic Places, Inventory - Nomination Form, Star Gazers House. pp. 6. Enter "public" for ID and "public" for password to access the site.