See her Clear Springs: A Memoir (1999); A. Wilhelm, Bobbie Ann Mason: A Study of the Short Fiction (1998); J. Price, Understanding Bobbie Ann Mason (1998).
See his papers, ed. by R. A. Rutland (3 vol., 1970); biographies by K. M. Rowland (1892, repr. 1964), R. A. Rutland (1961, repr. 1963), and F. Henri (1971).
See biography by his daughter, Virginia Mason (1903).
See J. W. Dean, ed., Captain John Mason (1887, repr. 1972).
See his narrative of the Pequot War in A Brief History of the Pequot War (1736, repr. 1971); biography by L. B. Mason (1935).
Lowell Mason had four sons, all active musically. The two eldest, Daniel Gregory and Lowell, formed a publishing company in New York City. Lowell, the third son, Henry, and Emmons Hamlin founded Mason & Hamlin, a firm that first made organs and later made pianos. The youngest son, William Mason, 1829-1908, b. Boston, was a distinguished concert pianist and teacher. He studied in Europe with Liszt and others. With Theodore Thomas he organized a chamber-music ensemble that did much to interest Americans in chamber music. He wrote Memories of a Musical Life (1901).
The son of Henry Mason, Daniel Gregory Mason, 1873-1953, b. Brookline, Mass., was important as a composer, writer, and lecturer. He studied with John K. Paine at Harvard and with D'Indy in Paris. In 1905 he joined the faculty of Columbia, where he was professor of music from 1929 to 1940. His writings include Music in My Time (1938) and The Quartets of Beethoven (1947). Among his compositions are the festival overture Chanticleer (1928); three symphonies, of which the third, known as Lincoln Symphony (1936), is outstanding; and chamber music.
Originally, the boundary between Maryland and Pennsylvania. The 233-mi (375-km) line was surveyed by Charles Mason and Jeremiah Dixon in 1765–68 to define the disputed boundaries between the land grants of the Penns, proprietors of Pennsylvania, and the Baltimores, proprietors of Maryland. The term was first used in congressional debates leading to the Missouri Compromise (1820) to describe the dividing line between the slave states to its south and the free-soil states to its north. It is still used as the figurative dividing line between the North and South.
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(born Nov. 3, 1798, Fairfax county, Va., U.S.—died April 28, 1871, Alexandria, Va.) U.S. politician. A grandson of George Mason, he practiced law in his native Virginia from 1820. He served in the state legislature (1826, 1828–32), the U.S. House of Representatives (1837–39), and the U.S. Senate (1847–61). An advocate of secession, he resigned his Senate seat in 1861. Appointed Confederate commissioner to England, he was captured at sea with John Slidell aboard the Trent and imprisoned for two months (see Trent Affair). Released in 1862, he remained in England until 1865 but was unable to win support for the Confederate cause.
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(born May 15, 1909, Huddersfield, Yorkshire, Eng.—died July 27, 1984, Lausanne, Switz.) British film actor. After studying architecture at the University of Cambridge, he made his screen debut in Late Extra (1935) and soon became a star in British films such as The Man in Grey (1943), The Seventh Veil (1945), and Odd Man Out (1947). He moved to Hollywood in the late 1940s but continued to make films in Britain as well. Noted for his urbane characterizations of flawed individuals, he appeared in more than 100 movies, including Madame Bovary (1949), A Star Is Born (1954), North by Northwest (1959), Lolita (1962), Georgy Girl (1966), The Boys from Brazil (1978), and The Verdict (1982).
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George Mason, detail of an oil painting by L. Guillaume after a portrait by J. Hesselius; in the elipsis
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(born Feb. 28, 1797, near Buckland, Mass., U.S.—died March 5, 1849, South Hadley) U.S. pioneer in higher education for women. She studied at various academies, supporting herself from age 17 by teaching. Her success as a teacher and administrator, and the demand for the young women she had trained, led to her plan for a permanent instructional institution for women. The school she founded in South Hadley, Mass., opened in 1837 as the Mount Holyoke Female Seminary (the forerunner of Mount Holyoke College), and she served as its principal until her death.
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(born Feb. 28, 1797, near Buckland, Mass., U.S.—died March 5, 1849, South Hadley) U.S. pioneer in higher education for women. She studied at various academies, supporting herself from age 17 by teaching. Her success as a teacher and administrator, and the demand for the young women she had trained, led to her plan for a permanent instructional institution for women. The school she founded in South Hadley, Mass., opened in 1837 as the Mount Holyoke Female Seminary (the forerunner of Mount Holyoke College), and she served as its principal until her death.
Learn more about Lyon, Mary (Mason) with a free trial on Britannica.com.
(born Nov. 3, 1798, Fairfax county, Va., U.S.—died April 28, 1871, Alexandria, Va.) U.S. politician. A grandson of George Mason, he practiced law in his native Virginia from 1820. He served in the state legislature (1826, 1828–32), the U.S. House of Representatives (1837–39), and the U.S. Senate (1847–61). An advocate of secession, he resigned his Senate seat in 1861. Appointed Confederate commissioner to England, he was captured at sea with John Slidell aboard the Trent and imprisoned for two months (see Trent Affair). Released in 1862, he remained in England until 1865 but was unable to win support for the Confederate cause.
Learn more about Mason, James Murray with a free trial on Britannica.com.
(born May 15, 1909, Huddersfield, Yorkshire, Eng.—died July 27, 1984, Lausanne, Switz.) British film actor. After studying architecture at the University of Cambridge, he made his screen debut in Late Extra (1935) and soon became a star in British films such as The Man in Grey (1943), The Seventh Veil (1945), and Odd Man Out (1947). He moved to Hollywood in the late 1940s but continued to make films in Britain as well. Noted for his urbane characterizations of flawed individuals, he appeared in more than 100 movies, including Madame Bovary (1949), A Star Is Born (1954), North by Northwest (1959), Lolita (1962), Georgy Girl (1966), The Boys from Brazil (1978), and The Verdict (1982).
Learn more about Mason, James with a free trial on Britannica.com.
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George Mason, detail of an oil painting by L. Guillaume after a portrait by J. Hesselius; in the elipsis
Learn more about Mason, George with a free trial on Britannica.com.
The Mason–Dixon Line (or "Mason and Dixon's Line") is a demarcation line between four U.S. states, forming part of the borders of Pennsylvania, Maryland, Delaware, and West Virginia (then part of Virginia). It 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. Popular speech, especially since the Missouri compromise of 1820 (apparently the first official usage of the term "Mason's and Dixon's Line"), uses the Mason-Dixon Line symbolically as a cultural boundary between the Northern United States and the Southern United States (Dixie).
In 1732 the proprietary governor of Maryland, Charles Calvert, 5th Baron Baltimore, signed an agreement with William Penn's sons which drew a line somewhere in between, and also renounced the Calvert claim to Delaware. But later Lord Baltimore claimed that the document he signed did not contain the terms he had agreed to, and refused to put the agreement into effect. Beginning in the mid-1730s, violence erupted between settlers claiming various loyalties to Maryland and Pennsylvania. The border conflict between Pennsylvania and Maryland would be known as Cresap's War.
The issue was unresolved until the Crown intervened in 1760, ordering Frederick Calvert, 6th Baron Baltimore to accept the 1732 agreement. As part of the settlement, the Penns and Calverts commissioned the English team of Charles Mason and Jeremiah Dixon to survey the newly established boundaries between the Province of Pennsylvania, the Province of Maryland, Delaware Colony and parts of Colony and Old Dominion of Virginia.
After Pennsylvania abolished slavery in 1781, the western part of this line and the Ohio River became a border between free and slave states, although Delaware remained a slave state.
Mason and Dixon's actual survey line began to the south of Philadelphia, Pennsylvania, and extended from a benchmark east to the Delaware River and west to what was then the boundary with western Virginia.
The surveyors also fixed the boundary between Delaware and Pennsylvania and the approximately north–south portion of the boundary between Delaware and Maryland. Most of the Delaware–Pennsylvania boundary is a circular arc, and the Delaware–Maryland boundary does not run truly north-south because it was intended to bisect the Delmarva Peninsula rather than follow a meridian.
The Maryland–Pennsylvania boundary is an east-west line with an approximate mean latitude of 39° 43' 20" N (Datum WGS 84). In reality, the east-west Mason-Dixon line is not a true line in the geometric sense, but is instead a series of many adjoining lines, following a path between latitude 39° 43' 15" N and 39° 43' 23" N; a surveyor or mapper might call it an approximate rhumb line. As such, the line approximates a segment of a small circle upon the surface of the (also approximately) spherical Earth. An observer standing on such a line and viewing its path toward an unobstructed horizon would perceive it to bend away from his line of sight, an effect of the inequality between the amount of curvature to his left and right. Among parallels of latitude, only the Equator is a great circle and would not exhibit this effect.
The surveyors also extended the boundary line to run between Pennsylvania and colonial western Virginia (which became West Virginia during the American Civil War, on June 20, 1863), though this was contrary to their original charter; this extension of the line was only confirmed later (see Yohogania County for details).
The Mason–Dixon Line was marked by stones every mile and ”crownstones” every five miles, using stone shipped from England. The Maryland side says (M) and the Delaware and Pennsylvania sides say (P). Crownstones include the two coats-of-arms. Today, while a number of the original stones are missing or buried, many are still visible, resting on public land and protected by iron cages.
Mason and Dixon confirmed earlier survey work which delineated Delaware's southern boundary from the Atlantic Ocean to the ”Middle Point” stone (along what is today known as the Transpeninsular Line). They proceeded nearly due north from this to the Pennsylvania border.
Later the line was marked in places by additional benchmarks and survey markers. The lines have been resurveyed several times over the centuries without substantive changes to Mason and Dixon's work. The stones may be a few to a few hundred feet east or west of the point Mason and Dixon thought they were; in any event, the line drawn from stone to stone forms the legal boundary.
According to Dave Doyle at the National Geodetic Survey, part of the National Oceanic and Atmospheric Administration, the common corner of Pennsylvania, Maryland, and Delaware, at The Wedge is marked by Boundary Monument #87. The marker ”MDP Corner” dates from 1935 and is offset on purpose.
Doyle said the Maryland–Pennsylvania Mason–Dixon Line is exactly:
and Boundary Monument #87 is on that parallel, at:
Visitors to the tripoint are strongly encouraged to first obtain permission from the nearest landowner.
The line was established to end a boundary dispute between the British colonies of Maryland and Pennsylvania/Delaware. Due to incorrect maps and confusing legal descriptions, the royal charters of the three colonies overlapped. Maryland was granted the territory north of the Potomac River/Watkins Point up to the fortieth parallel; Pennsylvania was granted land extending northward from a point "12 miles north of New Castle Towne," which is located south of the fortieth parallel. The most serious problem was that the Maryland claim would put Philadelphia, which became the major city in Pennsylvania, within Maryland. A protracted legal dispute between the Calvert family, which controlled Maryland, and the Penn family, which controlled Pennsylvania and the "Three Lower Counties" (Delaware), was ended by the 1750 ruling that the boundary should be fixed as follows:
The disputants engaged an expert British team, astronomer Charles Mason and surveyor Jeremiah Dixon, to survey what became known as the Mason–Dixon Line. It cost the Calverts of Maryland and the Penns of Pennsylvania the immense sum of £3,500 to have 244 miles surveyed with such accuracy. To them the money was well spent, for in a new country there was no other way of establishing ownership.
The Mason–Dixon line is made up of four segments corresponding to the terms of the settlement: Tangent Line, North Line, Arc Line, and 39° 43' N parallel. The most difficult task was fixing the Tangent Line, as they had to confirm the accuracy of the Transpeninsular Line mid-point and the Twelve-Mile Circle, determine the tangent point along the circle, then actually survey and monument the border. They then surveyed the North and Arc Lines. They did this work between 1763 and 1767. This actually left a small wedge of land in dispute between Delaware and Pennsylvania until 1921.
In April 1765 Mason and Dixon began their survey of the more famous Maryland-Pennsylvania line. They were commissioned to run it for a distance of five degrees of longitude west from the Delaware River, fixing the western boundary of Pennsylvania (see the entry for Yohogania County). However, in October 1767 at Dunkard Creek near Mount Morris, Pennsylvania, nearly 244 miles (392 km) west of the Delaware, a group of Native Americans forced them to quit their progress. In 1784, surveyors David Rittenhouse and Andrew Ellicott and their crew completed the survey of the Mason-Dixon line to the southwest corner of Pennsylvania, five degrees from the Delaware River. Other surveyors continued west to the Ohio River. The section of the line between the southwestern corner of Pennsylvania and the river is the county line between Marshall and Wetzel counties, West Virginia.
The boundary between Pennsylvania and Maryland was resurveyed in 1849, then again in 1900.
The Missouri Compromise of 1820 created the political conditions which made the Mason-Dixon Line important to the history of slavery. It was during the Congressional debates leading up to the compromise that the term "Mason-Dixon line" was first used to designate the entire boundary between free states and slave states.
On November 14, 1963, during the bicentennial of the Mason–Dixon Line, U.S. President John F. Kennedy opened a newly completed section of Interstate 95 where it crossed the Maryland-Delaware border. It was his last public appearance before the one 8 days later in Dallas, Texas, where he was assassinated. The Delaware Turnpike and the Maryland portion of the new road were each later designated as the John F. Kennedy Memorial Highway.
The Mason-Dixon line became symbolic of the division between the "free states" and "slave states" from the Missouri Compromise until the end of the American Civil War. Pennsylvania abolished slavery before the end of the American Revolution while Maryland, Delaware, Kentucky, and Missouri remained slave states until the end of the war.
After the Civil War, the line continued to be considered a cultural boundary. Some have imagined it continuing westward from Pennsylvania down the Ohio River to the Mississippi River, and crossing the Mississippi to place Arkansas, Louisiana and Texas south of the line. Debate whether border states such as Missouri, Kentucky, Maryland and West Virginia belong on the north or south side of this boundary line continues to this day.

