**Robert Simson** was a Scottish mathematician best known for the *Simson line* of a triangle, even though he was not the first discoverer of it.

- Simson entered the University of Glasgow as a student on 3 March 1702, being 14 years old at the time, and studied under the regent John Tran.
- He then set to work to study mathematics seriously, but he had to do this on his own, since at that time, for some reason, there were no lectures given on the subject by the professor Robert Sinclair.
- During his first year as a student in Glasgow Robert Simson was involved in a rather interesting incident which shows that, even before the Union of the Parliaments, Scottish as well as English students celebrated the 5th of November with fireworks.
- On emerging from a close that night Robert was hurt in the face by shot from a pistol belonging to a fellow student Arthur Tran, who with a group of other students was firing a pistol and letting off squibs.
- It is generally supposed that Robert Simson attended the University as a student for a period of about eight years until 1710, this was not an unusual period of study at the time.
- In 1710 Professor Robert Sinclair resigned, and Simson was offered the chair.
- 1712), Savilian Professor of Geometry at Oxford, William Jones, and finally Humphrey Ditton (1675-1715), Mathematical Master at Christ's Hospital, with whom Simson was particularly friendly.
- Simson's work on Euclid's porisms was published in 1723 in the Philosophical Transactions of the Royal Society, and his restoration of the Loci Plani of Apollonius appeared in 1749.
- Simson also set himself the task of preparing an edition of Euclid's Elements in as perfect a form as possible, and his edition of Euclid's books 1-6, 11 and 12 was for many years the standard text and formed the basis of textbooks on geometry written by other authors.
- Simson's lectures were delivered in Latin, at any rate at the beginning of his career.
- For Simson the best vehicle for presenting a mathematical argument was geometry and, although he was familiar with the recent developments in algebra and the infinitesimal calculus, he preferred to express himself in geometrical terms wherever possible.
- For fifty years Simson lectured five days a week during term time to his two main classes.
- Simson was a good looking man, tall of stature and favouring light coloured cloths.
- Simson was a sociable man.
- Robert Simson was the first person to be appointed to the office of Clerk (later known as Clerk of Senate), which he took up in 1728 and only demitted when he retired in 1761.
- Simson remained in good health until a few years before his death, during which period he had to employ an amanuensis to assist him in revising his geometrical writings.
- A year before he retired from the Chair of Mathematics, Simson had proposed that his colleague James Buchanan, the Professor of Oriental Languages, should relieve him of his teaching duties on condition of succeeding to the Chair when he retired, but Buchanan died before any action was taken.
- Before Simson retired in 1761 he stipulated that his Assistant James Williamson should succeed him, and this was agreed.
- Robert Simson died in his eight-first year and was buried in the neighbouring Blackfriars burial ground, where a marble tombstone, bearing a long laudatory Latin inscription, was raised in his memory.
- Simson bequeathed his very large library of books and papers to the University of Glasgow, where they comprise the valuable Simson Bequest.
- However the Simson line does not appear in his work but Poncelet in Propriétés Projectives says that the theorem was attributed to Simson by Servois in the Gergonne's Journal.
- The University of St Andrews awarded Simson an honorary Doctorate of Medicine in 1746.

Born 14 October 1687, West Kilbride, Ayrshire, Scotland. Died 1 October 1768, Glasgow, Scotland.

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Origin Scotland, Special Numbers And Numerals

**O’Connor, John J; Robertson, Edmund F**: MacTutor History of Mathematics Archive