seamus dubhghaill

Promoting Irish Culture and History from Little Rock, Arkansas, USA


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Birth of Henry John Stephen Smith, Mathematician & Amateur Astronomer

Henry John Stephen Smith, mathematician and amateur astronomer, is born in Dublin on November 2, 1826. He is remembered for his work in elementary divisorsquadratic forms, and Smith–Minkowski–Siegel mass formula in number theory. In matrix theory he is visible today in having his name on the Smith normal form of a matrix. He is also first to discover the Cantor set.

Smith is the fourth child of John Smith (1792–1828), a barrister, who dies when Henry is two. His mother, Mary Murphy (d.1857) from Bantry Bay, very soon afterward moves the family to England. He has thirteen siblings, including Eleanor Smith, who becomes a prominent educational activist. He lives in several places in England as a boy. His mother does not send him to school but educates him herself until age 11, at which point she hires private tutors. In 1841, at the age of 15, he is admitted to Rugby School in Warwickshire, where Thomas Arnold is the school’s headmaster. This comes about because his tutor, Henry Highton, takes up a housemaster position there.

At the age of 19 Smith wins an entrance scholarship to Balliol College, Oxford. He graduates in 1849 with high honours in both mathematics and classics. He is fluent in French having spent holidays in France, and he takes classes in mathematics at the College of Sorbonne in Paris during the 1846–47 academic year. He is unmarried and lives with his mother until her death in 1857. He then brings his sister, Eleanor, to live with him as housekeeper at St. Giles.

Smith remains at Balliol College as a mathematics tutor following his graduation in 1849 and is soon promoted to Fellow status.

In 1861, Smith is promoted to the Savilian Chair of Geometry at the University of Oxford. In 1873, he is made the beneficiary of a fellowship at Corpus Christi College, Oxford, and gives up teaching at Balliol College.

In 1874, Smith becomes Keeper of the University Museum and moves, along with his sister, to the Keeper’s House on South Parks Road in Oxford.

On account of his ability as a man of affairs, Smith is in demand for academic administrative and committee work: he is Keeper of the Oxford University Museum of Natural History, a Mathematical Examiner for the University of London, a member of a Royal Commission to review scientific education practice, a member of the commission to reform University of Oxford governance, chairman of the committee of scientists overseeing the Meteorological Office and twice president of the London Mathematical Society.

Smith dies in Oxford on February 9, 1883. He is buried in St. Sepulchre’s Cemetery in Oxford.


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Birth of Alexander Mitchell, Engineer & Inventor

Alexander Mitchell, Irish engineer who from 1802 is blind, is born in Dublin on April 13, 1780. He is known as the inventor of the screw-pile lighthouse.

Mitchell’s family moves to Belfast while he is a child. He receives his formal education at Belfast Academy where he excels in mathematics. He begins to notice that his eyesight is failing. By the age of 16 he can no longer read and by the age of 22 he is completely blind.

Undeterred, Mitchell borrows £100 and starts up a successful business making bricks in the Ballymacarrett area of Belfast. This enables him to start building his own houses and he completes approximately twenty in the city. It is during this period that his talent for inventing comes to the fore and he fabricates several machines for use in brickmaking and the building trade.

Mitchell patents the screw pile in 1833, for which he later gains some fame. The screw-pile is used for the erection of lighthouses and other structures on mudbanks and shifting sands, including bridges and piers. His designs and methods are employed all over the world from the Portland, Maine breakwater to bridges in Bombay. Initially it is used for the construction of lighthouses on Maplin Sands in the Thames Estuary in 1838, at Fleetwood Lancashire (UK) Morecambe Bay in 1839 and at Belfast Lough where his lighthouse is finished in July 1844.

In 1848 Mitchell is elected member of the Institution of Civil Engineers (ICE) and receives the Telford Medal the following year for a paper on his invention.

In May 1851 Mitchell moves to Cobh to lay the foundation for the Spit Bank Lighthouse. The success of these undertakings leads to the use of his invention on the breakwater at Portland, the viaduct and bridges on the Bombay, Baroda and Central India Railway and a broad system of Indian telegraphs.

Mitchell becomes friendly with astronomer John Thomas Romney Robinson and mathematician George Boole.

Mitchell dies at Glen Devis near Belfast on June 25, 1868, and is buried in the old Clifton graveyard in Belfast. His wife and daughter predecease him.


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Death of John Purser, Mathematician & Professor

John Purser, Irish mathematician and professor at Queen’s College, Belfast, dies in Dublin on October 18, 1903.

Purser is born in Dublin on August 24, 1835, the son of John Tertius Purser (1809–1893), the general manager of the well-known A Guinness, Son & Co. brewery, and Anna Benigna Fridlezius (1803-1881). He is educated in a wealthy family, which includes artists, as his cousin Sarah Purser, or engineers, as his brother-in-law John Purser Griffith. He is the brother of mathematician Frederick Purser. He receives his early education at the private boarding school run by his uncle, Dr. Richard W. Biggs, at Devizes, Wiltshire. He completes his schooling at Devizes and begins his university studies at Trinity College, Dublin, graduating BA in mathematics in 1856. He is the best mathematician of his year at the University and in 1855 he gains the Lloyd Exhibition.

Purser becomes a tutor to the four sons of William Parsons, 3rd Earl of Rosse (1800-1867) in 1857. Lord Rosse’s 72-inch reflecting telescope, built in 1845 and colloquially known of as the “Leviathan of Parsonstown,” is the world’s largest telescope when it is built and continues to hold this distinction until the early 20th century. As well as acting as tutor to the children, Purser does become involved in Lord Rosse’s interest in astronomy but never does any observing.

In 1863, Purser is appointed professor of mathematics at Queen’s College, Belfast, a position he maintains until his retirement in 1901.

Purser is much better known as a teacher than as a researcher, and he has a good number of notable students, including Sir Joseph Larmor, theoretical physicist who serves as Lucasian Professor of Mathematics at the University of Cambridge; Charles Parsons, the inventor of the steam turbine; Sir John Henry MacFarland, who becomes Chancellor of the University of Melbourne; and William McFadden Orr.

Purser never marries. When his father dies on April 5, 1893, Rathmines Castle passes to him. He dies at Rathmines Castle on October 18, 1903, a very wealthy man. In his will he leaves £100,000 to his brother Frederick Purser, £40,000 to his sister Anna Griffith and £5,000 to each of her children. In addition to the money, he owns property in Blessington Street, Essex Street and Eustace Street which he leaves to his brother-in-law John Purser Griffith. Other properties and interests that he owns he divides between his brother Frederick and his sister Anna. After his death, his sister Anna and her husband John Purser Griffith move into Rathmines Castle although, at this time, its ownership has gone to Frederick Purser. After Frederick dies in August 1910, the Castle and his considerable wealth passes to Anna.

(Pictured: Portrait of John Purser painted by the artist Sarah Purser, daughter of Tertius Purser’s brother Benjamin Purser. The portrait hangs in Queen’s College, Belfast.)


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Birth of Mary Field Parsons, Countess of Rosse

Mary Parsons (née Field), Countess of Rosse, Anglo-Irish amateur astronomer, architect, furniture designer, and pioneering photographer, is born on April 14, 1813, at Heaton Hall, Heaton, Bradford, West Yorkshire, England. Often known simply as Mary Rosse, she is one of the early practitioners of making photographs from waxed-paper negatives.

Field is the daughter of John Wilmer Field, a wealthy estate owner. She has a sister, Delia, and they are educated at home by Susan Lawson, a governess who encourages her creativity and broad interests, including astronomy. The sisters are joint heirs to their father’s fortune.

Through her family Field meets William Parsons, then Lord Oxmantown and the future 3rd Earl of Rosse, an Anglo-Irish astronomer and naturalist, and they are married on April 14, 1836, her 23rd birthday. In February 1841, Lord Oxmantown succeeds his father in the family peerage to become the 3rd Earl of Rosse. She, Baroness Oxmantown since her marriage, thus now becomes the Countess of Rosse.

In the early 1840s the couple becomes interested in astronomy, and the Countess of Rosse helps her husband build a number of giant telescopes, including the so-called Leviathan of Parsonstown, that is considered a technical marvel in its time. The author, Henrietta Heald, contends that she is not only a financial support to the building of the telescope, but is also involved in a practical and intellectual capacity. The Leviathan of Parsontown is completed in 1845 and holds the record as the world’s largest telescope for over 70 years. It is mentioned in Jules Verne’s science fiction novel, From the Earth to the Moon.

The Countess of Rosse is an accomplished blacksmith, which is very unusual for higher class women of the time, and she may have constructed some of the iron work that supports the telescope. Other metal cast items around the castle grounds are designed by her, including bronze gates.

During the Great Famine of 1845–47 in Ireland, the Countess of Rosse is responsible for keeping over five hundred men employed in work in and around Birr Castle, where she and her husband live.

The Countess of Rosse creates a huge dining room at Birr Castle in which to entertain scientific guests, which becomes increasingly used when Lord Rosse becomes President of the Royal Society of London in 1848. Guests include mathematician William Rowan Hamilton, who writes her a sonnet about his experience of gazing through the Leviathan.

In 1842, Lord Rosse begins experimenting in daguerreotype photography, possibly learning some of the art from his acquaintance William Henry Fox Talbot. In 1854, he writes to Fox Talbot saying that the Countess too has just commenced photography and sends some examples of her work. Fox Talbot replies that some of her photographs of the telescope “are all that can be desired.”

The Countess of Rosse becomes a member of the Dublin Photographic Society, and in 1859 she receives a silver medal for “best paper negative” from the Photographic Society of Ireland. Many examples of her photography are in the Birr Castle Archives. Much of the topography of Birr Castle that she portrayed has changed very little, and it is possible to compare many of her photographs with the actual places. She records the Leviathan in her photographs including one image showing her three sons, Clere, Randal and Charles along with her sister-in-law, Jane Knox, standing upright at the mouth of the telescope.

The Countess of Rosse gives birth to eleven children, but only four survive to adulthood:

Mary, Dowager Countess of Rosse, dies in 1885.


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Birth of John Lighton Synge, Mathematician & Physicist

John Lighton Synge FRSC FRS, mathematician and physicist, whose seven-decade career includes significant periods in Ireland, Canada, and the United States, is born in Dublin on March 23, 1897. He is a prolific author and influential mentor and is credited with the introduction of a new geometrical approach to the theory of relativity.

Synge is born into a prominent Church of Ireland family. His uncle, John Millington Synge, is a famous playwright. He is more distantly related to the winner of the 1952 Nobel Prize in Chemistry, Richard Laurence Millington Synge. He is a great-great-great-grandson of the mathematician and bishop Hugh Hamilton.

Synge attends St. Andrew’s College, Dublin and in 1915 enters Trinity College Dublin (TCD). He is elected a Foundation Scholar his first year, which is unusual as it is normally won by more advanced students. While an undergraduate at TCD, he spots a non-trivial error in Analytical Dynamics of Particles and Rigid Bodies, a textbook by E. T. Whittaker, who had recently taught there, and notifies Whittaker of the error. In 1919 he is awarded a BA in Mathematics and Experimental Physics, and also a gold medal for outstanding merit. In 1922 he is awarded an MA, and in 1926 a Sc.D., the latter upon submission of his published papers up to then.

In 1918, Synge marries Elizabeth Eleanor Mabel Allen. She is also a student at TCD, first of mathematics, then of history, but family finances forced her to leave without graduating. Their daughters Margaret (Pegeen), Cathleen and Isabel are born in 1921, 1923 and 1930 respectively. The middle girl grows up to become the distinguished Canadian mathematician Cathleen Synge Morawetz.

Synge is appointed to the position of lecturer at Trinity College, and then accepts a position at the University of Toronto in 1920, where he is an assistant professor of mathematics until 1925. There he attends lectures by Ludwik Silberstein on the theory of relativity, stimulating him to contribute “A system of space-time co-ordinates,” a letter in Nature in 1921.

Synge returns to Trinity College Dublin, in 1925, where he is elected to a fellowship and is appointed the University Professor of Natural Philosophy (later to be known as “physics”). He is a member of the American Mathematical Society and the London Mathematical Society. He is treasurer of the Royal Irish Academy in 1929. He goes back to Toronto in 1930, where he is appointed Professor of Applied Mathematics and becomes Head of the Department of Applied Mathematics. In 1940, he supervises three Chinese students, Guo Yonghuai, Qian Weichang and Chia-Chiao Lin, who later become leading applied mathematicians in China and the United States.

Synge spends some of 1939 at Princeton University, and in 1941, he is a visiting professor at Brown University. In 1943 he is appointed as Chairman of the Mathematics Department of Ohio State University. Three years later he becomes Head of the Mathematics Department of the Carnegie Institute of Technology in Pittsburgh, where John Nash, Jr. is one of his students. He spends a short time as a ballistic mathematician in the United States Air Force between 1944 and 1945.

Synge returns to Ireland in 1948, accepting the position of Senior Professor in the School of Theoretical Physics at the Dublin Institute for Advanced Studies. This school had been set up in 1940, and had several outstanding members, including Erwin Schrödinger, a contributor to quantum mechanics, who is also a Senior Professor.

Synge makes outstanding contributions to different fields of work including classical mechanics, general mechanics and geometrical optics, gas dynamics, hydrodynamics, elasticity, electrical networks, mathematical methods, differential geometry, and Albert Einstein‘s theory of relativity. He studies an extensive range of mathematical physics problems, but his best-known work revolves around using geometrical methods in general relativity.

Synge is one of the first physicists to seriously study the interior of a black hole, and his early work is cited by both Martin David Kruskal and George Szekeres in their independent discoveries of the true structure of the Schwarzschild black hole. Synge’s later derivation of the Szekeres-Kruskal metric solution, which is motivated by a desire to avoid “using ‘bad’ coordinates to obtain ‘good’ coordinates,” has been generally under-appreciated in the literature, but is adopted by Chandrasekhar in his black hole monograph.

In pure mathematics, Synge is perhaps best known for Synge’s theorem, which concerns the topology of closed orientable Riemannian manifold of positive sectional curvature. When such a space is even-dimensional and orientable, the theorem says it must be simply connected. In odd dimensions, it instead says that such a space is necessarily orientable.

Synge also creates the game of Vish in which players compete to find circularity (vicious circles) in dictionary definitions.

Synge retires in 1972. He receives many honours for his works. He is elected as a fellow of the Royal Society of London in 1943. He is elected as a fellow of the Royal Society of Canada, and in 1943 is the first recipient of the society’s Henry Marshall Tory Medal, as one of the first mathematicians working in Canada to be internationally recognised for his research in mathematics. In 1954 he is elected an honorary fellow of Trinity College Dublin. He is president of the Royal Irish Academy from 1961 until 1964. The Royal Society of Canada establishes the John L. Synge Award in his honour in 1986.

Synge dies on March 30, 1995, in Dublin, exactly one week after his ninety-eighth birthday.


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Birth of Irish Mathematician James Thomson

James Thomson, Irish mathematician notable for his role in the formation of the thermodynamics school at the University of Glasgow, Is born on November 13, 1786, in Ballynahinch, County Down, in what is now Northern Ireland. He is the father of the engineer and physicist James Thomson and the physicist William Thomson, 1st Baron Kelvin.

Born into an Ulster Scots family, Thomson is the fourth son of Agnes Nesbit and James Thomson, a small farmer, at Annaghmore, near Ballynahinch, County Down, in Ulster. His early education is from his father. At the age of 11 or 12 he finds out for himself the art of dialling. His father sends him to a school at Ballykine, near Ballynahinch, kept by Samuel Edgar, father of John Edgar. Here he soon rises to be an assistant.

Wishing to become a minister of the Presbyterian church, Thomson enters the University of Glasgow in 1810, where he studies for several sessions, supporting himself by teaching in the Ballykine school during the summer. He graduates MA in 1812, and in 1814 he is appointed headmaster of the school of arithmetic, bookkeeping, and geography in the newly established Royal Belfast Academical Institution. In 1815 he is Professor of Mathematics in its collegiate department. Here he proves himself as a teacher. In 1829 the honorary degree of LL.D. is conferred upon him by the University of Glasgow, where in 1832 he is appointed Professor of Mathematics. He holds this post until his death on January 12, 1849.

Thomson is buried with his family on the northern slopes of the Glasgow Necropolis to the east of the main bridge entrance. The grave is notable due to the modern memorial to Lord Kelvin at its side.

Thomson is the author of schoolbooks that have passed through many editions including Arithmetic (1819), Trigonometry, Plane and Spherical (1820), Introduction to Modern Geography (1827), The Phenomena of the Heavens (1827), The Differential and Integral Calculus (1831), and Euclid (1834).

A paper, “Recollections of the Battle of Ballynahinch, by an Eye-witness,” which appears in the Belfast Magazine for February 1825, is from his pen.


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Birth of Mathematician William McFadden Orr

William McFadden Orr, mathematician, is born May 2, 1866, at Ballystockart, Comber, County Down, in what is now Northern Ireland.

Orr is the eldest son of Fletcher Blakely Orr of Ballystockart, a unitarian farmer and millowner, and Elizabeth Orr, daughter of David Lowry, farmer, of Ballymacashin, County Down. He attends a local national school, spends two years at an intermediate school in Newtownards, and then attends Methodist College Belfast (MCB). He wins a Royal University of Ireland (RIU) scholarship in mathematics in 1883 and graduates in 1885 from Queen’s College Belfast, a constituent college of the RUI. He then matriculates at St. John’s College, Cambridge, where he is Senior Wrangler in 1888 and comes in first in part two of the Mathematical Tripos in 1889. Two years later he is elected to a fellowship at St. John’s, and the same year is appointed professor of applied mathematics at the Royal College of Science for Ireland in Dublin. When the Royal College is merged with University College Dublin (UCD) in October 1926, he becomes professor of pure and applied mathematics, a position he holds until his retirement in 1933.

Orr’s 1909 publication Notes on Thermodynamics for Students is seen as epitomising his style of teaching, with its emphasis on logical rigour and clear statement of underlying assumptions. Known for his generosity to staff and students who encounter difficulties, he is nonetheless a strict disciplinarian who abhors idleness and valued stoicism. He is elected Fellow of the Royal Society (FRS) in 1909 and is awarded an honorary degree of D.Sc. from Queen’s University Belfast (QUB) in 1919.

In 1892, Orr marries Elizabeth Campbell of Melbourne, Australia, whose father, Samuel Campbell, is from County Down. They live at 19 Pembroke Road, Dublin, and have three daughters. He dies at Douglas, Isle of Man on August 14, 1934, and is interred in Mount Jerome Cemetery, Dublin. He is survived by his two daughters.

(From: “Orr, William McFadden” contributed by Paul Rouse, Dictionary of Irish Biography, http://www.dib.ie)


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Death of John Hewitt Jellett, Mathematician & Priest

John Hewitt Jellett, Irish mathematician whose career is spent at Trinity College Dublin (TCD), where he rises to the rank of Provost, dies in Dublin on February 19, 1888. He is also a priest in the Church of Ireland.

Jellett is born at Cashel, County Tipperary, on December 25, 1817, the son of Rev. Morgan Jellett and his wife Harriette Townsend, daughter of Hewitt Baldwin Poole of County Cork, by his wife Dorothea Morris. He is the eldest brother of Hewitt Poole Jellett, Serjeant-at-law (Ireland) and Chairman of the Quarter Sessions for County Laois, and of the Venerable Henry Jellett, Archdeacon of Cloyne. He is educated at Kilkenny College and at TCD, where he becomes a fellow in 1840.

Jellett marries his cousin on his mother’s side, Dorothea Charlotte Morris Morgan, daughter of James Morgan, on July 7, 1855. The marriage produces seven children. His son, William Morgan Jellett, is a member of the Parliament of the United Kingdom and is the father of the celebrated artist Mainie Jellett, and of Dorothea Jellett, director of the orchestra of the Gaiety Theatre, Dublin. Another son Henry Holmes Jellett is a civil engineer in British India. His daughter Harriette Mary Jellett is the wife of the noted Irish physicist George Francis FitzGerald. Another daughter Eva Jellett is the first woman to graduate with a degree in medicine from Trinity and goes on to practice as a doctor in India.

Jellett graduates B.A. in mathematics in 1837, M.A. 1843, B.D. 1866, and D.D. 1881. He is ordained a priest in 1846. In 1848 he is elected to the chair of natural philosophy at TCD, and in 1868 he receives the appointment of commissioner of Irish national education.

In 1851 Jellett is awarded the Cunningham Medal of the Royal Irish Academy for his work on the “Calculus of Variations.” The society later elects him their president, a position he holds from 1869 to 1874.

In 1870, on the death of Dr. Thomas Luby, Jellett is co-opted a Senior Fellow, and thus a member of the Board of TCD. William Ewart Gladstone‘s government in February 1881 appoints him provost of Trinity. In the same year he is awarded a Royal Medal by the Royal Society.

After the disestablishment of the Church of Ireland by the Irish Church Act 1869, Jellett takes an active part in the deliberations of the general synod and in every work calculated to advance its interests. He is an able mathematician and writes A Treatise of the Calculus of Variations (1850), and A Treatise on the Theory of Friction (1872), as well as several papers on pure and applied mathematics, articles in the Transactions of the Royal Irish Academy. He also writes some theological essays, sermons, and religious treatises, of which the principals are An Examination of some of the Moral Difficulties of the Old Testament (1867), and The Efficacy of Prayer (1878).

Jellett dies of blood poisoning at the provost’s house, TCD, on February 19, 1888, and is buried in Mount Jerome Cemetery on February 23. The funeral procession is the largest that ever left Trinity.

(Pictured: “John Hewitt Jellett,” oil on canvas by Sarah Purser)


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Death of Mathematician Sir William Rowan Hamilton

Sir William Rowan Hamilton, Irish mathematician, Andrews Professor of Astronomy at Trinity College, Dublin, and Royal Astronomer of Ireland, who makes important contributions to classical mechanics, optics, and algebra, dies in Dublin on September 2, 1865, following a severe attack of gout.

Hamilton is born in Dublin on August 4, 1805, the fourth of nine children born to Sarah Hutton (1780–1817) and Archibald Hamilton (1778–1819). He is part of a small but well-regarded school of mathematicians associated with Trinity College, Dublin, which he enters at age eighteen. He is said to have shown immense talent at a very early age. Astronomer Bishop Dr. John Brinkley remarks of the 18-year-old Hamilton, “This young man, I do not say will be, but is, the first mathematician of his age.”

Trinity College awards him two Optimes, or off-the-chart grades. He studies both classics and mathematics and is appointed Professor of Astronomy just prior to his graduation. He then takes up residence at Dunsink Observatory where he spends the rest of his life.

Although Hamilton regards himself as a pure mathematician rather than a physicist, his work is of major importance to physics, particularly his reformulation of Newtonian mechanics, now called Hamiltonian mechanics. This work has proven central to the modern study of classical field theories such as electromagnetism, and to the development of quantum mechanics. In pure mathematics, he is best known as the inventor of quaternions.

Hamilton’s scientific career includes the study of geometrical optics, classical mechanics, adaptation of dynamic methods in optical systems, applying quaternion and vector methods to problems in mechanics and in geometry, development of theories of conjugate algebraic couple functions, solvability of polynomial equations and general quintic polynomial solvable by radicals, the analysis on Fluctuating Functions, linear operators on quaternions and proving a result for linear operators on the space of quaternions, which is a special case of the general theorem which today is known as the Cayley–Hamilton theorem. He also invents Icosian calculus, which he uses to investigate closed edge paths on a dodecahedron that visit each vertex exactly once.

Hamilton retains his faculties unimpaired to the very last, and steadily continues the task of finishing the Elements of Quaternions which occupies the last six years of his life. He dies in Dublin on September 2, 1865, following a severe attack of gout precipitated by excessive drinking and overeating. He is buried in Mount Jerome Cemetery in Dublin.


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Birth of John Purser, Mathematician & Professor

John Purser, Irish mathematician and professor at Queen’s College, Belfast, is born in Dublin on August 24, 1835.

Purser is the son of John Tertius Purser (1809–1893), the general manager of the well known A Guinness, Son & Co. brewery, and Anna Benigna Fridlezius (1803-1881). He is educated in a wealthy family, which includes artists, as his cousin Sarah Purser, or engineers, as his brother-in-law John Purser Griffith. He is the brother of mathematician Frederick Purser. He receives his early education at the private boarding school run by his uncle, Dr. Richard W. Biggs, at Devizes, Wiltshire. He completes his schooling at Devizes and begins his university studies at Trinity College, Dublin, graduating BA in mathematics in 1856. He is the best mathematician of his year at the University and in 1855 he gains the Lloyd Exhibition.

Purser becomes a tutor to the four sons of William Parsons, 3rd Earl of Rosse (1800-1867) in 1857. Lord Rosse’s 72-inch reflecting telescope, built in 1845 and colloquially known of as the “Leviathan of Parsonstown,” is the world’s largest telescope when it is built and continues to hold this distinction until the early 20th century. As well as acting as tutor to the children, Purser does become involved in Lord Rosse’s interest in astronomy but never does any observing.

In 1863, Purser is appointed professor of mathematics at Queen’s College, Belfast, a position he maintains until his retirement in 1901.

Purser is much better known as a teacher than as a researcher, and he has a good number of notable students, including Sir Joseph Larmor, theoretical physicist who serves as Lucasian Professor of Mathematics at the University of Cambridge; Charles Parsons, the inventor of the steam turbine; Sir John Henry MacFarland, who becomes Chancellor of the University of Melbourne; and William McFadden Orr.

Purser never marries. When his father dies on April 5, 1893, Rathmines Castle passes to him. He dies at Rathmines Castle on October 18, 1903, a very wealthy man. In his will he leaves £100,000 to his brother Frederick Purser, £40,000 to his sister Anna Griffith and £5,000 to each of her children. In addition to the money, he owns property in Blessington Street, Essex Street and Eustace Street which he leaves to his brother-in-law John Purser Griffith. Other properties and interests that he owns he divides between his brother Frederick and his sister Anna. After his death, his sister Anna and her husband John Purser Griffith move into Rathmines Castle although, at this time, its ownership has gone to Frederick Purser. After Frederick dies in August 1910, the Castle and his considerable wealth passes to Anna.

(Pictured: Portrait of John Purser painted by the artist Sarah Purser, daughter of Tertius Purser’s brother Benjamin Purser. The portrait hangs in Queen’s College, Belfast.)