Thursday, 5 November 2026

  This was written just before the election in 2008, and most of the polls had settled into a 53-45 spread for Obama, which, for all my nay-saying in this blog, was very close.  




Well, we are almost to the election, which means an end, finally, to the interminable projection polls. Ok, I actually like statistics, but I'm not sure I accept that political polls are not playing a little fast and loose with the assumptions that are needed to compute confidence intervals. I love it when the election goes the wrong way and they have to come up with scenarios for WHY they blew it. Of course with so many of them out there making 95% confidence intervals, about five percent of the ones you hear SHOULD be wrong... but I think there is more to the problem than just that.

I came across a blog from Iowahawk ( I didn't provide a link because my students come here and some of his language is not the sort of thing I display for my students..they know all the words anyway, but they won't hear them from me) that had a nice expression of what I felt, so I stole parts of it shamelessly...


Statisticians love balls and urns. A typical Stats 101 midterm, for example, usually includes a question along these lines:

"You take a simple random sample of 1000 balls from an urn containing 120,000,000 red and blue balls, and your sample shows 450 red balls and 550 blue balls. Construct a 95% confidence interval for the true proportion of blue balls in the urn."
From this the typical Intro stats student can deduce that they are 95% certain the real proportion of blue balls in that urn is 55%, plus or minus 3.1% .

"This is, for all intents and purposes, how political pollsters compute the mysterious "margin of error," which has everything to do (and only to do) with pure mathematical sampling error. If you look at the formula above and round it just a smidge, you get a simple rule of thumb for the margin of error of a sampled probability:
Margin of Error = 1 / sqrt(n)

So if the sample size is 400, the margin of error is 1/20 = 5%; if the sample size is 625 the margin of error is 1/25 = 4%; if the sample size is 1000, it's about 3%.


"It works pretty well if you're interested in hypothetical colored balls in hypothetical urns, or survival rates of plants in a controlled experiment, or defects in a batch of factory products. It may even work well if you're interested in blind cola taste tests. But what if the thing you are studying doesn't quite fit the balls & urns template?"



What if 40% of the balls have personally chosen to live in an urn that you legally can't stick your hand into?

What if 50% of the balls who live in the legal urn explicitly refuse to let you select them?

What if the balls inside the urn are constantly interacting and talking and arguing with each other, and can decide to change their color on a whim?

What if you have to rely on the balls to report their own color, and some unknown number are probably lying to you?

What if you've been hired to count balls by a company who has endorsed blue as their favorite color?

What if you have outsourced the urn-ball counting to part-time temp balls, most of whom happen to be blue?

What if the balls inside the urn are listening to you counting out there, and it affects whether they want to be counted, and/or which color they want to be?

If one or more of the above statements are true, then the formula for margin of error simplifies to

Margin of Error = Who the heck knows?

On This Day in Math - November 5

   

Bonfire night in my old area in East Anglia

I hope you enjoy the absence of pupils ... the total oblivion of them for definite intervals is a necessary condition for doing them justice at the proper time.
~James Clerk Maxwell (every teacher knows how true this statement is.)

The 309th day of the year; 3095= 2,817,036,000,549. It is the smallest number whose fifth power contains all the digits 0 to 9. (Students, is there a smaller number that contains all the digits for some other power?)

  is prime  *Prime Curios

309 = 155^2 - 154^2 = 53^2-50^2

And 309 is the number of primes less than 2^11 = 2058, and the number of fractions in a Farey Sequence with a largest denominator of 31   See A Curious Property of Vulgar Fractions 

309 is 303 plus the sum of digits of 303, and also 294 plus the sum of digits of 294.



EVENTS
1603 Edmund Bruce, a Scot traveling in Italy, in a letter to Kepler put forward some ideas based on Bruno’s cosmology. He maintained that the Sun, at the center of the planetary orbits, turns on its axis and thereby drives the planets around in their orbits, the more distant more slowly than those closer to the Sun. The light of the stars, he went on, is due to their motion, not their matter.


In 1662, Robert Hooke was appointed Curator of Experiments to the Royal Society, London. The position was established as a provision of the Royal Charter given by King Charles II (passed by the Great Seal on 15 July 1662) to incorporate the Royal Society. The Society was the successor of the Society for the Promoting of Physico-Mathematical Experimental Learning formed by at a meeting of a dozen scientist on 28 Nov 1660 at Gresham College. Hooke was required to demonstrate three or four experiments at every meeting of the Society, starting without recompense until 1664 when the Society was in a position to do so. Hooke's genius produced a wealth of original ideas over the following 15 years.*TIS
The Curious Life of Robert Hooke: The Man Who Measured London



1666 Leibniz received his doctor’s degree at age 20 for his essay on a new method (the historical) of teaching law from the University of Altdorf near Nuremberg. He had studied law at his home town University of Leipzig, entering at 15, but left at 20 when he was denied his doctorate, officially on account of his youth. Altdorf offered him a professorship in law, but he declined. [Bell, Men of Mathematics, 122] *VFR

In 1824, the Rensselaer School was founded in Troy, N.Y., by Stephen van Rensselaer becoming the first engineering college in the U.S. It opened on 3 Jan 1825, with the purpose of instructing persons, who may choose to apply themselves, in the application of science to the common purposes of life." The first class of 10 students graduated on 26 Apr 1826. The first director and senior professor was Amos Eaton who served from Nov 1824 - 10 May 1842. The name of Renssalaer Institute was adopted on 26 Apr 1832, and Renssalaer Polytechnic Institute on 8 Apr 1861.*TIS
*From Little Acorns, Great Oaks Grow


1828 Augustus DeMorgan, age 22, gave his introductory lecture, “On the study of mathematics,” at London University (UCL). It described the position which mathematics held in a person’s education. DeMorgan was the first to hold the university’s chair in mathematics, being chosen from 32 candidates, even though he was by far the youngest. See the chapter on DeMorgan in A History of Mathematics Education in England (1982), by. A. G. Howson [p. 82].*VFR
Among the students in his classes was fourteen year old James Joseph Sylvester. Sylvester had to be interviewed by the instructor to determine his knowledge of mathematics to determine his placement. He must have impressed DeMorgan who placed him in his highest senior class. *James Joseph Sylvester: Jewish Mathematician in a Victorian World By Karen Hunger Parshall




1859 Benjamin Peirce suggests variations on modern paper-clip as symbols for pi and  e. *J. D. Runkle's Mathematical Monthly


1884 Evelyn Lamb's research seems to indicate that the first review for E A Abbott's "Flatland" was on this date. I can't find that review, but 3 days later this one appeared

The Academy (November 8, 1884), p. 302.
"Flatland is a world inhabited by beings whose experience of space is limited to two dimensions. In this book a native of this strange region has undertaken to describe its peculiarities to us dwellers in `Spaceland.' It seems the male Flatlanders are plane rectilineal figures, varying in shape according to their position in the social scale, or, what in Flatland is the same thing, to their degree of intellectual development; the lowest class being isosceles triangles, and the highest class, or priesthood, being polygons which have so many sides that they are accounted circles. The Flatland women, being deplorably lacking in intellect, are not figures at all, but merely straight lines. Of course, the inhabitants of two-dimensional space cannot see each other as figures, but only as straight lines. For the means by which they can infer one another's true shape, and for the manners and institutions of Flatland, the reader must be referred to the book itself. The historian of Flatland is by rank and figure `a square,' and he has a grandson, a clever hexagon, who one day startles him with a suggestion that space may have a third dimension, and that beings may exist who are capable of seeing the inside of a closed figure. The notion is angrily rejected as absurd; but the `Square' afterwards undergoes a miraculous experience that introduces him to the threefold space which he was previously unable to imagine. Guided by the analogy of his own experience, he ventures to suggest to the inhabitants of `Spaceland' that a fourth dimension may have real existence, though it is to them as inconceivable as the third dimension once was to himself. The `Square' has forgotten to tell us by what means he has managed to make himself intelligible to tri-dimensional mankind, and one or two other weak points might easily be found in his story; but, on the whole, the idea is very cleverly worked out, with many happy satiric touches, and the book is much more entertaining than this account of it will lead the reader to suppose."

John A Adam commented, "It's a wonderful little book, and the movies, Flatland and Sphereland, are excellent. Also, there's a book, Sphereland, by Dionysus Burger written in the same spirit as Flatland."

 

*http://www.math.brown.edu/~banchoff




In 1891, Marie Curie enrolled in the Sorbonne, two days before her 24th birthday. She has been out of school for 5 years, is now in a foreign country (France instead of her homeland of Poland), has barely enough money to survive, and even faints from hunger on at least one occasion in the classroom. Yet she eventually graduated at the top of her class. Then on this same day in 1906, (see below) she delivered her first lecture at the Sorbonne as the first female physics teacher in the school's history.*TIS

In 1906, at 1:30 pm, Marie Curie gave her inaugural lecture as the first woman lecturer at the Sorbonne. She explained the theory of ions in gases and her treatise on radioactivity to 120 students, public and press. Following the accidental death of her husband, Pierre Curie, she had been invited to occupy the Physics chair at the Sorbonne that he had held. Madame Curie, by now a Nobel prize winner and authority on radioactivity, continued the work she started with her husband.*TIS




1895  George B. Selden is granted the first U.S. patent for an automobile. *the painter flynn
He filed for a patent on May 8, 1879 with a witness who  was a local bank-teller, George Eastman, later to become famous for the Kodak camera. His application included not only the engine but its use in a 4-wheeled car. He then filed a series of amendments to his application which stretched out the legal process resulting in a delay of 16 years before the patent.  *Wik

In the small town of Memphis, Michigan there is a roadside marker for another, and perhaps the earliest self-propelled four-wheeler in this great automobile state. It reads, "The Thing" was a self-propelled vehicle, powered by a steam engine, built in 1884-1885 by Thomas and John Clegg (father and son) in their Memphis machine shop. The historical marker states that The Thing was "the first recorded self-propelled vehicle in Michigan (and perhaps the country)" and that "It ran about 500 miles before Clegg dismantled it and sold the engine to a creamery."

*Wikipedia





Add caption
1955 Doc Emmett Brown conceives of the Flux Capacitor which would power the time traveling DeLorean and the following Jules Verne Train in the "Back to the Future" movies. Brown came up with the idea of the flux capacitor after slipping and bumping his head while standing on his toilet to hang a clock. The idea came to him in a vision he had after being knocked out. He drew an inverted Y-shape with wires and stated "flux compression". He also performed some mild calculations on the paper. *Wik (HT to Colin@icecolbeveridge & @arbesman for the heads up on this one)  The flux capacitor can be seen lit up behind Marty just before temporal displacement.

1965 climate scientists summarized the risks associated with rising carbon pollution in a report for Lyndon Baines Johnson. "a section on atmospheric carbon dioxide and climate change, written by prominent climate scientists Roger Revelle, Wallace Broecker, Charles Keeling, Harmon Craig, and J Smagorisnky. Reviewing the document today, one can’t help but be struck by how well these scientists understood the mechanisms of Earth’s climate change 50 years ago." *theguardian.com

In 1992, the discovery of chemical evidence of 5000-year-old beer found at Godin Tepe in the Zagros mountains of Iran was reported in the journal Nature. Beer was the preferred fermented beverage of the ancient Sumerians. Chemical evidence was found from an organic residue inside a pottery vessel that had apparently been used for beer fermentation or storage. Some grooves were found inside the double-handled jar which contained a pale yellowish residue that gave a positive test for oxalate ion. Calcium oxalate, only slightly water-soluble is a principal component of sediment that settles from barley beer. In 1991, evidence for the earliest grape wine of had been found in the same area, and to be of similar age, about 3500 - 3100 BC. *TIS
Beer Receipt,  Alulu beer receipt recording a purchase of "best" beer from a brewer, c. 2050 BC, from the Sumerian city of Umma in ancient Iraq.  (Make it Lite, I'm trying to lose weight!)




2018  A second earth made vehicle has passed the boundaries of the heliosphere into the space between stars.  Seven years after Voyager 1 crossed the same boundary, Voyager 2 passed the heliopause with loads of new equipment to measure the physical nature of the space outside the heliosphere.  Light from our sun that reaches Earth in about 8 minutes, will need another 16+ hours to reach Voyager 2.  Path viewed from above the Solar System





BIRTHS

1846 Edward Singleton Holden (November 5, 1846 – March 16, 1914) was an American astronomer. Born in St. Louis, Missouri in 1846 to Jeremiah and Sarah Holden. From 1862-66, he attended Washington University in St. Louis, where he obtained a B.S. degree. He later trained at West Point in the class of 1870.In 1873 he became professor of mathematics at the US Naval Observatory, where he made a favorable impression on Simon Newcomb. He was director of Washburn Observatory at the University of Wisconsin–Madison from 1881 to 1885. He was elected a member of the American National Academy of Sciences in 1885.
On August 28, 1877, a few days after Asaph Hall discovered the moons of Mars Deimos and Phobos, he claimed to have found a third satellite of Mars. Further analysis showed large mistakes in his observations.
He was president of the University of California from 1885 until 1888, and the first director of the Lick Observatory from 1888 until the end of 1897. Meanwhile in 1893 while at the observatory he published a book on Mughal Emperors, The Mogul emperors of Hindustan, A.D. 1398- A.D. 1707. He resigned as a result of internal dissent over his management among his subordinates. While at the Lick Observatory, he was the founder of the Astronomical Society of the Pacific and its first President (1889–1891).
In 1901 he became the librarian of the United States Military Academy at West Point, where he remained until his death.
His cousin, George Phillips Bond, was director of Harvard College Observatory.
He discovered a total of 22 NGC objects during his work at Washburn Observatory.
He wrote many books on popular science (and on other subjects, such as flags and heraldry), including science books intended for children. For example the book Real Things In Nature. A Reading Book of Science for American Boys and Girls published in 1916.*Wik



1848 James Whitbread Lee Glaisher (5 November 1848 – 7 December 1928) son of James Glaisher, the meteorologist, was a prolific English mathematician. He was educated at St Paul's School and Trinity College, Cambridge, where he was second wrangler in 1871. Influential in his time on teaching at the University of Cambridge, he is now remembered mostly for work in number theory that anticipated later interest in the detailed properties of modular forms. He published widely over other fields of mathematics. He was the editor-in-chief of Messenger of Mathematics. *TIS



1866 Alfred Tauber (5 Nov 1866 in Pressburg, now Bratislava, Slovakia , 1942 in Theresienstadt, Germany now Terezin, Czech Republic) Tauber's research was on function theory and potential theory. He obtained important results on divergent series and the name 'Tauberian Theorems' was coined by Hardy and Littlewood. This all came out of his work on Abel's limit theorem which dated back to 1826. The conditions which Tauber gave to allow him to prove the converse of Abel's limit theorem on power series are now known as 'Tauberian conditions' and appeared in Ein Satz aus der Theorie der unendlichen Reihen (1897). This is by far his most significant piece of work. Further major results in this area were obtained by Norbert Wiener. Of lesser importance is Tauber's work on differential equations and the gamma function, but let us give the title of one of his papers on this latter topic, namely über die unvollständigen Gammafunktionen (1906). The date of his death is unknown. He was sent by the Nazis to Theresienstadt concentration camp on June 28 1942. Just after Tauber arrived the entire non-Jewish population of 3,700 of Theresienstadt was evacuated and he was one of 53,000 inhabitants of the camp. *SAU



1906 Fred Lawrence Whipple (5 Nov 1906; 30 Aug 2004) was an American astronomer who proposed the "dirty snowball" model for comet nuclei. In the 1930s, using a new, two-station method of photography, he determined meteor trajectories and found that nearly all visible meteors are made up of fragile material from comets, and that none come from beyond the solar system. Whipple suggested (1950) that comets have icy cores inside thin insulating layers of dirt, and that jets of material ejected as a result of solar heating were the cause of orbital changes. This model was confirmed in 1986 when spacecraft flew past comet Halley. Whipple’s work on tracking artificial satellites led to improved knowledge of the shape of the earth and greatly improved positions on earth. *TIS




1930 John Frank Adams (5 Nov 1930 in Woolwich, London, England - 7 Jan 1989 Near Brampton, Huntingdonshire, England) was an English algebraic topologist who pioneered methods for calculating the homotopy of spheres *SAU



1952 Robert Wayne Thomason (5 Nov 1952 Tulsa, Oklahoma, USA – Nov 1995 Paris, France) was an American mathematician who worked on algebraic K-theory. His results include a proof that all infinite loop space machines are in some sense equivalent, and his work on the Quillen–Lichtenbaum conjecture.*Wik







DEATHS

1526 Scipione del Ferro (6 February 1465 – 5 November 1526) was an Italian mathematician who first discovered a method to solve the depressed cubic equation. There are no surviving scripts from del Ferro. This is in large part due to his resistance to communicating his works. Instead of publishing his ideas, he would only show them to a small, select group of friends and students. It is suspected that this is due to the practice of mathematicians at the time of publicly challenging one another. When a mathematician accepted another's challenge, each mathematician needed to solve the other's problems. The loser in a challenge often lost funding or his university position. Del Ferro was fearful of being challenged and likely kept his greatest work secret so that he could use it to defend himself in the event of a challenge.
Despite this secrecy, he had a notebook where he recorded all his important discoveries. After his death in 1526, this notebook was inherited by his son-in-law Hannival Nave, who was married to del Ferro's daughter, Filippa. Nave was also a mathematician and a former student of del Ferro's, and he replaced del Ferro at the University of Bologna after his death. In 1543, Gerolamo Cardano and Ludovico Ferrari (one of Cardano's students) traveled to Bologna to meet Nave and learn about his late father-in-law's notebook, where the solution to the depressed cubic equation appeared.
Del Ferro also made other important contributions to the rationalization of fractions with denominators containing sums of cube roots.
He also investigated geometry problems with a compass set at a fixed angle, but little is known about his work in this area. *Wik



1800 Jesse Ramsden (6 Oct 1735, 5 Nov 1800) British pioneer in the design of precision tools. At 23, Ramsden chose to apprentice to a maker of mathematical instruments. By age 27 he had his own business in London and was known as the most skillful designer of mathematical, astronomical, surveying and navigational instruments in the 18th Century. He is best known for the design of a telescope and microscope eyepiece (ocular) still commonly used today and bearing his name. The French scientist N. Cassegrain proposed a design of a reflecting telescope in 1672. It was Ramsden, however, 100 years later, who found that this design reduces blurring of the image caused by the sphericity of the lenses or mirrors. He also built lathes, barometers, manometers and assay balances.
Sextant, brass, by Jesse Ramsden, c. 1770. In the Adler Planetarium and Astronomy Museum, Chicago. 37 × 38.5 × 10 cm, with a radius of 31 cm.



1857 Edmund Davy FRS (1785 – 5 November 1857) was a professor of Chemistry at the Royal Cork Institution from 1813 and professor of chemistry at the Royal Dublin Society from 1826. He discovered acetylene, as it was later named by Marcellin Berthelot. He was also an original member of the Chemical Society, and a member of the Royal Irish Academy. He was a cousin of Humphry Davy, and spent eight years as operator and assistant to Humphry Davy in the Royal Institution laboratory. (Humphry Davy's younger brother, Dr. John Davy, (24 May 1790 - 24 Jan 1868) also was a chemist who spent some time (1808–1811) assisting Humphry in his chemistry research at the Royal Institution. John was the first to prepare and name phosgene gas.) *Wik



1879 James Clerk Maxwell (13 Jun 1831, 5 Nov 1879)Scottish physicist and mathematician. Maxwell's researches united electricity and magnetism into the concept of the electro-magnetic field. In London, around 1862, Maxwell calculated that the speed of propagation of an electromagnetic field is approximately that of the speed of light. He proposed that the phenomenon of light is therefore an electromagnetic phenomenon. The four partial differential equations, now known as Maxwell's equations, first appeared in fully developed form in Electricity and Magnetism (1873). He died relatively young; some of the theories he advanced in physics were only conclusively proved long after his death. Maxwell's ideas also paved the way for Einstein's special theory of relativity and the quantum theory. *TIS



1934 Walther Franz Anton von Dyck (6 Dec 1856 in Munich, Germany - 5 Nov 1934 in Munich, Germany) Von Dyck made important contributions to function theory, group theory (where a fundamental result on group presentations is named after him), topology (where he was influenced by the work of Riemann), and to potential theory. He made significant contributions to the Gauss-Bonnet theorem.
Another important project which von Dyck undertook was one to publish the complete works of Kepler, including all Kepler's letters. He undertook this in his role as class secretary of the Bayerische Akademie der Wissenschaften in 1906. This project has extended well beyond von Dyck's lifetime with Volume 7 appearing in 1953, and Volume 8 in 1963. *SAU

He was the 8th Rector of the Technical University of Munich. 

When von Dyck was a young mathematician studying under Felix Klein at Leipzig, Klein encouraged him to think about symmetry not just in geometry, but as an abstract system of operations. This advice inspired von Dyck’s 1882 paper, which gave the first modern axiomatic definition of a group — a turning point in algebra. *PB

Later, when von Dyck became a professor at the Technische Hochschule München, he was famous for his patient, fatherly manner with students. He was known to invite them to his home for discussions that drifted from mathematics into art, music, and philosophy. One visitor noted that von Dyck’s study was lined not with mathematical tomes but with paintings and musical scores — a reflection of his belief that “mathematics, like art, should reveal structure and harmony.” *Wik

Von Dyck is the son of the Bavarian painter Hermann Dyck.

The Dyck language in formal language theory is named after him, as are Dyck's theorem and Dyck's surface in the theory of surfaces, together with the von Dyck groups, the Dyck tessellations, Dyck paths, and the Dyck graph.





1981 Stanisław Mazur (born 1 January 1905, Lviv - 5 November 1981, Warsaw) was a Polish mathematician and a member of the Polish Academy of Sciences. He made important contributions to geometrical methods in linear and nonlinear functional analysis and to the study of Banach algebras. Mazur was also interested in summability theory, infinite games and computable functions.
Mazur was a student of Stefan Banach at University of Lwów. His doctorate, under Banach's supervision, was awarded in 1935.
Mazur was a close collaborator with Banach at Lwów and was a member of the Lwów School of Mathematics, where he participated in the mathematical activities at the Scottish Café. On 6 November 1936, Mazur posed the "basis problem" of determining whether every Banach space has a Schauder basis, with Mazur promising a "live goose" as a reward: Thirty-seven years later, a live goose was awarded by Mazur to Per Enflo in a ceremony that was broadcast throughout Poland.*Wik





1992 Jan Hendrik Oort (28 Apr 1900, 5 Nov 1992) was a Dutch physicist and astronomer, one of the most important figures in 20th-century efforts to understand the nature of the Milky Way Galaxy, who measured the rotation of the earth's galaxy and hypothesized an "Oort Cloud." In 1927 Oort analyzed motions of distant stars, found evidence for differential rotation and founded the mathematical theory of galactic structure. After World War II, he led the Dutch group which used the 21-cm line to map hydrogen gas in the Galaxy. They found the large-scale spiral structure, the galactic center, and gas cloud motions. In 1950 Oort proposed the now generally accepted model for the origin of comets. He continued researching galaxies until shortly before his death at 92. *TIS



2005 Arthur Taylor Winfree (May 15, 1942 – November 5, 2002) was a theoretical biologist at the University of Arizona. He was born in St. Petersburg, Florida, United States.
Winfree was noted for his work on the mathematical modeling of biological phenomena: from cardiac arrhythmia and circadian rhythms to the self-organization of slime mold colonies and the Belousov–Zhabotinsky reaction. Winfree was a MacArthur Fellow from 1984 to 1989 and shared the 2000 Norbert Wiener Prize in Applied Mathematics with Alexandre Chorin. *Wik
Among numerous awards he was a Westinghouse Science Talent Search Finalist in 1960, a John Simon Guggenheim Memorial Fellowship awardee in 1982, and shared the AMS-SIAM Norbert Wiener Prize in Applied Mathematics with A. Chorin in 2000. His obituary in Siam began: "When Art Winfree died in Tucson on November 5, 2002, at the age of 60, the world lost one of its most creative scientists. I think he would have liked that simple description: scientist. After all, he made it nearly impossible to categorize him any more precisely than that. He started out as an engineering physics major at Cornell (1965), but then swerved into biology, receiving his PhD from Princeton in 1970. Later, he held faculty positions in theoretical biology (Chicago, 1969-72), in the biological sciences (Purdue, 1972-1986), and in ecology and evolutionary biology (University of Arizona, from 1986 until his death). " *SIAM
He was the father of Erik Winfree, another MacArthur Fellow and currently a professor at the California Institute of Technology, and Rachael Winfree, currently an Assistant Professor in the Department of Entomology at Rutgers University.




*CHM=Computer History Museum
*FFF=Kane, Famous First Facts
*NSEC= NASA Solar Eclipse Calendar
*RMAT= The Renaissance Mathematicus, Thony Christie
*SAU=St Andrews Univ. Math History
*TIA = Today in Astronomy
*TIS= Today in Science History
*VFR = V Frederick Rickey, USMA
*Wik = Wikipedia
*WM = Women of Mathematics, Grinstein & Campbell

Wednesday, 4 November 2026

The Agony and the Obelus, or Much Ado about Notation

   


In November of 2019 I combined several blogs on Division to create some notes about the history of the topic.  I did not include notes on the history of the symbols commonly used for division, and today I corrected that oversight by including this post from 2015 about those symbols.  This information is now included in that much longer post. 

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Recently(2015) James Tanton posted a short article about problems that are circulating on the internet such as (and this is the one he used) "What is the value of the following expression: 62 ÷ 2(3)+4, and then asked, "Is the answer 10 or is the answer 58?" (my personal choice for historical reasons explained below is 3.6)

I don't care to argue the possible choices, although Professor Tanton does a good job of that in his blog, but I'm more interested in the history of some symbols for division he mentions there, obelus, vinculum, and one he didn't, the solidus. In particular, I'm interested in how the usage may have changed over time.

The earliest of the three terms to appear was the vinculum, and it came to us from the Hindu or Arabic mathematicians between the seventh and twelfth century. Here is how it is described by Jeff Miller's excellent web page on the first use of math symbols

Ordinary fractions without the horizontal bar. According to Smith (vol. 2, page 215), it is probable that our method of writing common fractions is due essentially to the Hindus, although they did not use the bar. Brahmagupta (c. 628) and Bhaskara (c. 1150) wrote fractions as we do today but without the bar.

The horizontal fraction bar was introduced by the Arabs. "The Arabs at first copied the Hindu notation, but later improved on it by inserting a horizontal bar between the two numbers" (Burton).

Several sources attribute the horizontal fraction bar to al-Hassar around 1200.


Now if you read Prof. Tanton's article, in which he ecstatically plugs the use of the vinculum, this is NOT what he is suggesting. The horizontal fraction bar made its way into western culture mostly on the back of Leonardo Fibonacci, who introduced both Arabic numbers, and some of their symbols. He referred to the fraction bar as "uirgula"; which has become the more modern word virgule, something like a wand or small rod. Unfortunatly, today the virgule is a term interchangeable with the older term solidus, and you recognize it as the slanted fraction bar, as in 3/5 (and occasionally with an s like bend such as the current symbol for integration), but all that would come much later.

The use of the vinculum that has the professor so excited was introduced around 1452 by Nicholas Chuquet The word is from the diminutive of vincere, to tie. Vinculum referred to a small cord for binding the hands or feet often used to keep cattle from wandering too far afield as they grazed in common areas. The meaning in math is mostly unchanged from that original meaning. The vinculum notation was once used in much the same way we now use parenthesis and brackets to "bind together" a group of numbers or symbols. Where today we might write (2x+3)5 the early users of the vinculum would write \( \underline {2x+3} \> 5 \) . Originally the line was placed under the items to be grouped although a bar over the grouping became the more lasting usage (and still is in the symbols for the radical sign for roots, and the repeat bar for decimal fractions). The bar on top seems to have been first used by Frans van Schooten.

 Dr Peterson at the Math Forum disagrees with calling the fraction bar a vinculum and has written, "I find no evidence, by the way, that it has ever properly been called a vinculum, which is a bar OVER an expression and serves to group it as parentheses do today. The fraction bar has something in common with that, but not enough in my opinion to justify the usage. With both vinculum and virgule used for other things, I just call it a fraction bar and am perfectly happy with that term!" (I'm OK with that, too.) Professor Tanton suggest that the vinculum, properly used, would eliminate questions about whether the answer to the question is 58, 10, (or 3.6).

The symbol "÷" which is used to indicate the operation of division is called an obelus. The word comes from the Greek word obelos, for spit or spike, a pointed stick used for cooking.  Perhaps because both are sharp and used for piercing meat, the word is sometimes used for a type of stabbing knife called a dagger and the same name is applied to an editing symbol that looks like a little dagger, †. The root also gives rise to the word obelisk for a pointed pillar of stone.
 The symbol(s) was used as an editing notation in early manuscripts, sometimes only as a line without the two dots, to indicate material which the editor thought might need to be "cut out". It had also found occasional use as a symbol for subtraction, for instance, by the famed Adam Riese as early as 1525, although he did not use it exclusively, intermixing the standard horizontal subtraction bar. It was first used as a division symbol by the Swiss mathematician Johann H Rahn in his Teutsche Algebra in 1659. 
There has long been a controversy about whether the symbol was introduced to him by John Pell. Cajori in his famous book on mathematical notation says there is no evidence for this, but some later historians, Jacqueline A. Stedall for one, now think it quite probably was Pell's creation. Pell had been Rahn's teacher in Zurich and they communicated on the book. Pell was famous for vacillating over whether he would, or would not, let his name be used on information he shared with others.

Let me make it clear I am not an authority on math history and do not read German,  but as I looked at the examples in Teutsche Algebra, I began to think that Pell/Rahn was not introducing this as a mathematical operator as it is now used. I could find no examples where the books used something like the expression in the problem in Prof. Tanton's blog.  Instead it seems to be used exclusively for a shorthand in explaining the operations used.  

Here is an image from page 76 of the Algebra, and it is using a method of teaching algebra by use of a 3 column format, which is certainly from the work of Pell. Each line contains a line number in the middle, instructions for what is being done to the equation in the left column, and the result in the right column. Today many solutions would simply show the sequence of equations in the right column.


The first two lines describe the given information. In the third line, the swirl is exponentiation and says that equation 1 has been squared on both sides. It is line 8 that provides the interesting note about the ÷ usage. The left column says equation 7 is divided by GG+1, but if you look at the right side, you will see that 7 ÷ GG+1 treats all the material to the right of the expression as if it were included in a parenthetical enclosure. Don't divide by GG and then add 1, but divide by the total quantity GG+1.

Now the two surprises here, for me, is that a) Rahn/Pell intends that the "÷" breaks the operation into two parts, the left and the right side as if they were enclosed in parentheses or marked with a vinculum. But the second, is that he doesn't use the expression as an operator in his expressions. Instead he uses the common horizontal division bar/vinculum common to others. So when did we begin to use "÷" as an operation with numbers. I do not have access to the great libraries that contain the early English arithmetics and algebras that eagerly adopted the obelus (it was almost never used anywhere except in English speaking countries), so I am hoping some of you who have more experience/access/knowledge can share so the rest of us will know. When did expressions like 62 ÷ 2(3)+4 first appear in arithmetic/algebra books? (At the moment I suspect they are a 20th century creation.)

So what about the Solidus. The slanted bar, "/", that is used for fractions, and division is often called a solidus. If you think that looks too much like solid to be a coincidence, you are right. The word comes from the same root. From the glory days of Rome to the Fall of the Byzantine Empire, the solidus was a gold coin ("solid" money). The origin of the modern word "soldier" is from the custom of paying them in solidus. According to Steven Schhwartzman's The Words of Mathematics, the coins reverse carried a picture of a spear bearer, with the spear going form lower left to upper right. He suggests that this is the relation to the slanted bar. Cajori seems to indicate (footnote 6, article 275, Vol 1) that the symbol is derived from the old version of the Latin letter s. This / symbol is also frequently called a virgule. Prior to the conversion to decimal coinage in the United Kingdom, it was common to use the symbol as a division between shillings and pence; for example 6/3 would indicate six shillings, three pence. Because of this use the symbol is also sometimes referred to as the shilling mark.
The solidus was introduced as a fraction/division symbol first suggested in De Morgan's Calculus of Functions he proposes the use of the slant line or "solidus" for printing fractions in the text, as in 3/4. In 188 G. G. Stokes put this into practice. Cayley would write to Stokes, "I think the solidus' looks very well indeed . . . ; it would give you a strong claim to be President of a Society for the prevention of Cruelty to Printers."
Stokes, in explaining his choice, says that the slanted bar is already in use for fractions, and simply uses it to expand to algebraic division. Then he states an explanation of the operational use, "In the use of the solidus, it seems convenient to enact that it shall as far as possible take the place of the horizontal bar for which it stands, and accordingly that what stands immediately on the two sides of it shall be regarded as welded into one." He then gives examples that make clear that he intends that a / bc means \(\frac{a}{bc} \) . He even gives a method for a period stop to indicate that the grouping has ended, so a/b.c would mean \(\frac{a}{b} (c) \)

So when did this end. When did we make the switch to the confusion of PEMDAS or BEMDAS or whatever it is called in your country. Cajori (1929) suggests that when using division and multiplication, "there is at present no agreement as to which sign shall be used first."  So it seems that the advent of memorized mnemonics independent of the symbol seems to have occurred later than that.  Similarly in 1923 the National Committee on Mathematical Requirements of the MAA recommended that the ÷ and : for division be replaced with the / solidus "(where the meaning is clear}."

So I looked on my bookshelf and found a 1939 copy of The New Curriculum Arithmetics, Grade Seven.  The authors are a professor of elementary education, a dean of a school of education, a superintendent of schools, and an elementary supervisor, surely folks who would be aware of the MAA recommendations, and yet, there was the ÷ all through the problem sets.  What was not there was a section on order of operations, or any problems that went beyond " number ÷ number."  No long strings of numbers and operations strung together.

Certainly the question was in the air, but unsettled in 1938 when Joseph A. Nyberg of Hyde Park HS in Chicago wrote in The Mathematics Teacher

 
Read the part in Italics again.... multiplication first, then division, without regard to the order.  That is not what you are telling your students today (I hope).  So maybe they were just working it out.... Nope, here is what N. J. Lennes had written in The American Mathematical Monthly in the article Discussions Relating to the Order of Operations in Algebra in February of 1917, 21 years earlier.

Better, right?  then turn the page, and find

So there is our old friend the obelus used exactly as I suspect Pell and Rahn had intended (if they intended it to be used as an operator at all), and lower down the solidus in the manner that Stokes suggested, but apparently used in a way the users thought distinguished it from the use of the obelus.  And you wonder why your students are confused?

I still have yet to resolve when the first use of the obelus appeared for division as an operator in an algebraic or arithmetic problem.  Anyone who has more information, please share. 
 I will continue my search as time allows and when I find out more I will continue to update this post. Thank you for any information you can share.

On This Day in Math - November 4

     




The shortest path between two truths in the real domain passes through the complex domain.
~Jacques Salomon Hadamard

The 308th day of the year; 308 is the sum of two consecutive primes.

If 18 circles are drawn in the plane, they can separate the plane into 308 regions. Student's might try to find the maximum number of regions for smaller numbers of circles, find a pattern, write f(n).

3083 + 3080 + 3088 is prime



EVENTS


1605  Remember, remember, the 5th of November,

Gunpowder, treason and plot.

I see no reason

Why gunpowder treason

Should ever be forgot.

Guy Fawkes, Guy Fawkes, 'twas his intent

To blow up the King and the Parliament

Three score barrels of powder below

Poor old England to overthrow

By God's providence he was catch'd

With a dark lantern and burning match

Holler boys, holler boys, let the bells ring

Holler boys, holler boys

God save the King!


On October 26, 1605, Lord Monteagle, a Roman Catholic noble, received an anonymous letter, delivered by an unknown messenger, which warned him not to attend Parliament, as it would receive “a terrible blow” intended “to punish the wickedness of this time.” Monteagle promptly notified Robert Cecil, 1st earl of Salisbury, the king’s chief minister. It was decided to allow the plot to develop, so that it might be fully uncovered. On November 4 the king, having been shown the letter, ordered Thomas Howard, 1st earl of Suffolk, to act. On the night of November 4–5, authorities discovered the massive store of gunpowder under Parliament and arrested Guy Fawkes.

The first weekend of November sees the annual celebration of Bonfire Night when around the country, people come together to make bonfires and watch them burn, whilst fireworks displays are seen and heard all over! *Britannica *Wik *PB notes 






1647  The earliest citation of Quadratic in English in the OED was a Nov 4, 1647 was by John Pell in a letter to C. Cavendish, "Not so high as a quadratic equation.".
QUADRATIC is derived from the Latin quadratus, meaning "square." In English, quadratic was used in 1668 by John Wilkins (1614-1672) in An essay towards a real character, and a philosophical language [London: Printed for Sa. Gellibrand, and for John Martyn, 1668]. He wrote: "Those Algebraical notions of Absolute, Lineary, Quadratic, Cubic"  *SAU



1833  On this day in 1833, William Hamilton read a paper to the Royal Irish Academy
 expressing complex numbers as algebraic couples, or ordered pairs of real numbers.  a + bi,  (a,b) *SAU
(The following makes me think Hamilton did not use the term "Complex number" at this time, but worked with a + bi form.)
Most of the 17th and 18th century writers spoke of a + bi as an imaginary quantity. Carl Friedrich Gauss (1777-1855) saw the desirability of having different names for ai and a + bi, so he gave to the latter the Latin expression numeros integros complexos. Gauss wrote:
...quando campus arithmeticae ad quantitates imaginarias extenditur, ita ut absque restrictione ipsius obiectum constituant numeri formae a + bi, denotantibus i pro more quantitatem imaginariam −1, atque a, b indefinite omnes numeros reales integros inter ∞
. Tales numeros vocabimus numeros integros complexos, ita quidem, ut reales complexis non opponantur, sed tamquam species sub his contineri censeatur.The citation above is from Gauss's paper "Theoria Residuorum Biquadraticorum, Commentatio secunda," Societati Regiae Tradita, Apr. 15, 1831, published for the first time in Commentationes societatis regiae scientiarum Gottingensis recentiones, vol. VII, Gottingae, MDCCCXXXII (1832)]. [Julio González Cabillón]

The term complex number was used in English in 1856 by William Rowan Hamilton. The OED2 provides this citation: Notebook in Halberstam & Ingram Math. Papers Sir W. R. Hamilton (1967) III. 657: "a + ib is said to be a complex number, when a and b are integers, and i = [sqrt] -1; its norm is a^2 + b^2; and therefore the norm of a product is equal to the product of the norms of its factors."






1845, Michael Faraday, working in his laboratory at the Royal Institution, hung a piece of heavy glass between the poles of an electro-magnet and observed that the glass aligned itself across the lines of force of the magnet. He further experimented on many other substances, with similar results, a phenomena that he named diamagnetism. These investigations showed Faraday that magnetism was inherent within matter. This led to his lecture "Thoughts on Ray-vibrations" in April 1846, which he expanded in the following years into his field theory of electro-magnetism. This was the progenitor for mathematical descriptions formed by Thomson, and especially for the seminal work of James Clerk Maxwell. *TIS



In 1869, the first issue was published of the journal Nature, editted by astronomer Sir Norman Lockyer. The first issue included articles on astronomy, plants, moths, science teaching in schools, an obituary for Thomas Graham, paleontology and meeting notices. Nature remains one of the most popular and well respected science journals in the world, printing research articles from across a wide range of scientific fields. *TIS




In 1879, James Jacob Ritty (1837-1918) with help from his brother John invented the first cash register, intended to combat stealing by bartenders in the Pony House Restaurant, his Dayton, Ohio saloon. His idea came on a cruise, when he saw a device that counted the revolutions of the ship's propeller. Their first model looked like a clock, but instead of the hands indicating hours and minutes, they indicated dollars and cents. Behind the dial two adding discs accumulated the total of the amounts recorded. Known as "the incorruptible cashier," with no cash drawer, it would show anyone within sight how much had been recorded. However, the Ritty brothers failed to sell their cash registers in large quantities - largely because shop staff distrusted this "thief trap"*TIS

1927, the first U.S. balloon flight ascent to exceed an altitude of 40,000-ft was made by Captain Hawthorne C. Gray of the U.S. Army Air Service, over Scott Field, Illinois. The nearly 2-hour free flight reached an altitude of 42,470-ft. The balloon had 80,000-cu.ft. capacity and used sand ballast. Because of trouble resulting in a descent that was too rapid, Gray parachuted out at 8,900-ft. Because Gray was not in command of the landing, the ascent did not make an official record.*TIS  
Another source gives : "Gray lost consciousness after his oxygen supply ran out and was killed in the crash." *Wik  Another says his balloon was lost by the planes tracking him.  His balloon was found later in Sparta Tennessee, with Gray's body curled in the bottom of the Gondola.
Captain Gray was awarded the Distinguished Flying Cross, posthumously, and is buried at the Arlington National Cemetery.*This Day in Aviation



1943 Robert Oppenheimer, working on the Manhattan Project, is so impressed by Richard Feynman that he writes his Physics dept chair at Berkeley to recommend that they hire him after the war. He includes in the recommendation, two comments by others of note; Hans Bethe stated that he would rather lose any two other men than Feynman from the project, and Wigner stated, "He is a second Dirac, only this time human." *Shaun Usher, Letters of Note web site




1952 Television makes its first foray into predicting a presidential election based on computer analysis of early returns. The Univac computer makes an incredibly accurate projection that the network doesn't think credible. Pre-election polls had predicted anything from a Democratic landslide to a tight race with the Demo candidate, Illinois Gov. Adlai Stevenson, slightly ahead of the Republican, five-star Gen. Dwight D. Eisenhower, Supreme Commander of Allied Forces in Europe in World War II. So it was a surprise at 8:30 p.m. Eastern time when Univac predicted Eisenhower would pile up 438 electoral votes to Stevenson's 93.
In New York, news boss Mickelson scoffed at putting the improbable prediction on air. In Philadelphia, Woodbury added new data to the mix. At 9 p.m. correspondent Charles Collingwood announced to the audience that Univac was predicting 8-7 odds for an Eisenhower win.
But wait! Back in Philly, Woodbury discovered that he'd mistakenly added a zero to Stevenson's totals from New York state. When he entered the correct data and ran it through Univac, he got the same prediction as before: Ike 438, Adlai 93,
As the evening wore on, an Eisenhower landslide gathered momentum. The final vote was 442 to 89. Univac was less than 1 percent off. *Wired.com
*J. Presper Eckert and Walter Cronkite discuss the UNIVAC prediction, CHM




1969 Pakistan issued a stamp honoring Alhazen (ab¯u-‘Al¯ıal-Hasan ibn al-Hasan ibn al-Haytham) (965–c. 1040), astronomer and optician. Pictured is a diagram showing the reflection of light. [Scott #281]. *VFR



BIRTHS

1744 Johann(III) Bernoulli (4 Nov 1744 in Basel, Switzerland
- 13 July 1807 in Berlin, Germany) wrote a number of works on astronomy and probability theory. Bernoulli wrote a number of works on astronomy, reporting on astronomical observations and calculations, but these are of little importance. Strangely his most important contributions were the accounts of his travels in Germany which were to have a historical impact.
In the field of mathematics he worked on probability, recurring decimals and the theory of equations. As in his astronomical work there was little of lasting importance. He did, however, publish the Leipzig Journal for Pure and Applied Mathematics between 1776 and 1789.
He was well aware of the famous mathematical line from which he was descended and he looked after the wealth of mathematical writings that had passed between members of the family. He sold the letters to the Stockholm Academy where they remained forgotten about until 1877. At that time when these treasures were examined, 2800 letters written by Johann(III) Bernoulli himself were found in the collection. *SAU (See "A Confusion of Bernoulli's" by the Renaissance Mathematicus.)




1765 Pierre-Simon Girard (Caen, 4 November 1765 – Paris, 30 November 1836) was a French mathematician and engineer, who worked on fluids. A prodigy who invented a water turbine at age 10, Girard worked as an engineer at the École Nationale des Ponts et Chaussées. He was in charge of planning and construction of the Amiens canal and the Ourcq canal. He collaborated with Gaspard de Prony on the Dictionnaire des Ponts et Chaussées (Dictionary of Bridges and Highways). He wrote works on fluids and on the strength of materials.*Wik



1908 Viktor Vladimirovich Wagner, also Vagner (4 November 1908 – 15 August 1981) was a Russian mathematician, best known for his work in differential geometry and on semigroups. *Wik

1921 Andrew Mattei Gleason (November 4, 1921 – October 17, 2008) was an American mathematician and the eponym of Gleason's theorem and the Greenwood–Gleason graph. After briefly attending Berkeley High School (Berkeley, California) he graduated from Roosevelt High School in Yonkers, then Yale University in 1942, where he became a Putnam Fellow. He subsequently joined the United States Navy, where he was part of a team responsible for breaking Japanese codes during World War II. He was appointed a Junior Fellow at Harvard in 1946, and later joined the faculty there where he was the Hollis Professor of Mathematicks and Natural Philosophy. He had the rare distinction among Harvard professors of having never obtained a doctorate. He retired in 1992. He is well-known for his work on Hilbert's fifth problem.*Wik



1933 The Honorable Sir Charles Kuen Kao,(November 4, 1933 – September 23, 2018) is a Chinese-born American and British physicist who pioneered in the development and use of fiber optics in telecommunications. Kao, known as the "Godfather of Broadband", "Father of Fiber Optics" or "Father of Fiber Optic Communications", was awarded half of the 2009 Nobel Prize in Physics for "groundbreaking achievements concerning the transmission of light in fibers for optical communication". Kao holds dual citizenship in Great Britain and the United States. *Wik





DEATHS

1652 Jan-Karel della Faille or Jean Charles de La Faille (1 March 1597 in Antwerp, Belgium - 4 Nov 1652 in Barcelona, Spain) was a Flemish Jesuit who was the first to determine the center of gravity of the sector of a circle. He proved that the centers of gravity of a sector of a circle, of a regular figure inscribed in it, of a segment of a circle, or of an ellipse lie on the diameter of the figure. These theorems are founded on a postulate from Luca Valerio's De centro gravitatis solidorum (1604). ... La Faille ended his work with four corollaries which revealed his ultimate goal: an examination of the quadrature of the circle. *SAU




1698 Erasmus Bartholin (13 Aug 1625, 4 Nov 1698) Danish physician, mathematician , physicist, died in Copenhagen. He discovered the optical phenomenon of double refraction. In 1669, Bartholin observed that images seen through Icelandic feldspar (calcite) were doubled and that, when the crystal was rotated, one image remained stationary while the other rotated with the crystal. Such behaviour of light could not be explained using Isaac Newton's optical theories of the time. Subsequently, this was explained as the effect of the polarisation of the light. Bartholin wrote a large number of mathematical works, and made astronomical observations, including the comets of 1665. He is also famed for his medical work, in particular his introduction of quinine in the fight against malaria.*TIS



1912 John Monroe Van Vleck (March 4, 1833–November 4, 1912) was an American mathematician and astronomer. He taught astronomy and mathematics at Wesleyan University in Middletown, Connecticut for more than 50 years (1853-1912), and served as acting university president twice. The Van Vleck Observatory (at Wesleyan University) and the crater Van Vleck on the Moon are named after him. *Wik



1917 William Du Bois Duddell (1872- 4 Nov 1917) English electrical engineer who invented the sensitive moving coil oscillograph able to photographically record a light spot tracing the oscillations of an electrical voltage, and other electrical instruments. He devised what may be regarded as the first electric musical instrument, the Singing Arc (1899), based on the sounds emitted by an electric carbon arc lamp when its supply voltage was varied. It was an outcome of his investigation to solve the problem of the undesirable humming or whining noises generated by carbon arc street lighting. This research discovered an associated principle of negative resistance. The audio frequencies were generated by switching suitable resonant circuits to the arc. Duddell died aged only 45 years old. *TIS



1954 Archibald Read Richardson (21 Aug 1881 in London, England - 4 Nov 1954 in Cape Town, South Africa) graduated from Imperial College London and then taught at the college. He was badly wounded in World War I. He became Professor of Mathematics at Swansea. His main interests were in algebra. *SAU
Richardson collaborated with Dudley E. Littlewood on invariants and group representation theory. They introduced the immanant of a matrix, studied Schur functions and developed the Littlewood–Richardson rule for their multiplication. *Wik






2011 Norman Foster Ramsey Jr (August 27, 1915 – November 4, 2011) American physicist who shared (with Wolfgang Paul and Hans Georg Dehmelt) the 1989 Nobel Prize for Physics in 1989 for "for the invention of the separated oscillatory fields method and its use in the hydrogen maser and other atomic clocks." His work produced a more precise way to observe the transitions within an atom switching from one specific energy level to another. In the cesium atomic clock, his method enables observing the transitions between two very closely spaced levels (hyperfine levels). The accuracy of such a clock is about one part in ten thousand billion. In 1967, one second was defined as the time during which the cesium atom makes exactly 9,192,631,770 oscillations.*TIS



2000 Ian Naismith Sneddon (8 December 1919 Glasgow, Scotland – 4 November 2000 Glasgow, Scotland) was a Scottish mathematician who worked on analysis and applied mathematics.

Sneddon was born in Glasgow on 8 December 1919, the son of Mary Ann Cameron and Naismith Sneddon. He was educated at Hyndland School in Glasgow

He studied mathematics and physics at the University of Glasgow, graduating with a BSc. He then went to the University of Cambridge, gaining an MA in 1941. From 1942 to 1945, during World War II, he served as a Scientific Officer to the Ministry of Supply. After the war he worked as a Research Officer for H H Wills Laboratory at the University of Bristol. In 1946, he began lecturing in Natural Philosophy (physics) at the University of Glasgow.

In 1950, he received a professorship at University College, North Staffordshire. In 1956, he returned to the University of Glasgow as Professor of Mathematics.

In 1958, he was elected a Fellow of the Royal Society of Edinburgh. His proposers were Robert Alexander Rankin, Philip Ivor Dee, William Marshall Smart and Edward Copson. He won the Society's Makdougall-Brisbane Prize for the period 1956-58. In 1983, he was further elected a Fellow of the Royal Society of London.

He retired in 1985, and died in Glasgow on 4 November 2000.





Credits :
*CHM=Computer History Museum
*FFF=Kane, Famous First Facts
*NSEC= NASA Solar Eclipse Calendar
*RMAT= The Renaissance Mathematicus, Thony Christie
*SAU=St Andrews Univ. Math History
*TIA = Today in Astronomy
*TIS= Today in Science History
*VFR = V Frederick Rickey, USMA
*Wik = Wikipedia
*WM = Women of Mathematics, Grinstein & Campbell