50 Fun Facts About James Clerk Maxwell

Maxwell's theory first described electricity, magnetism and what as manifestations of the same phenomenon?

His equations achieved what is called the second great unification in physics, after Newton's.

Maxwell's unification of light and electricity led him to predict the existence of what?

Heinrich Hertz would generate and detect them in the late 1880s, a decade after Maxwell's death.

Which 1865 paper showed electric and magnetic fields travel as waves at the speed of light?

In it he wrote that light "is an electromagnetic disturbance propagated through the field according to electromagnetic laws".

What velocity did Maxwell obtain for electromagnetic waves using the electrical data of his day?

It was close enough to the measured speed of light that he could "scarcely avoid the conclusion" that light was electromagnetic.

Who reduced Maxwell's twenty equations to the four now known as Maxwell's equations?

He also declared the electromagnetic potential arbitrary and in need of being "assassinated".

In which 1873 textbook did Maxwell's equations first appear in fully developed form?

Most of the work was done at Glenlair, between his London post and the Cavendish chair.

At what address in Edinburgh was Maxwell born on 13 June 1831?

The house now holds a museum run by the James Clerk Maxwell Foundation.

What was the name of the Kirkcudbrightshire estate where Maxwell grew up and worked?

The 1,500-acre estate is where the three-year-old asked of everything, "what's the go o' that?"

What nickname did Maxwell earn on his first day at Edinburgh Academy in homemade shoes?

He bore it without complaint for years; his lifelong friends Lewis Campbell and P. G. Tait ended his isolation.

At what age did Maxwell write his first scientific paper, on drawing oval curves with a piece of twine?

James Forbes presented it to the Royal Society of Edinburgh because the author was deemed too young to do so himself.

What did teenage Maxwell discover by viewing stressed gelatine through polarising prisms?

The technique reveals stress distribution inside structures and is still used by engineers.

To which Cambridge college did Maxwell transfer from Peterhouse for an easier fellowship?

There he was elected to the secret debating society known as the Cambridge Apostles.

Maxwell graduated in 1854 as Second Wrangler, behind which mathematician?

The two were later declared equal in the tougher Smith's Prize examination.

Which Cambridge tutor, nicknamed the "senior wrangler-maker", coached Maxwell from 1851?

The nickname reflected his record of producing top-ranked mathematics graduates.

Which three colours of light did Maxwell show would combine to make white, using Forbes's spinning tops?

The same additive primaries underpin colour television and every screen you own.

At which Aberdeen institution did Maxwell take the Chair of Natural Philosophy in 1856, aged 25?

He was a good 15 years younger than any other professor there and gave a weekly free lecture at the working men's college.

What did Maxwell conclude Saturn's rings must be made of, in the essay that won the 1859 Adams Prize?

He called them "brick-bats"; the Voyager flybys of the 1980s confirmed it more than a century later.

How much was the Adams Prize Maxwell won in 1859 for "On the stability of the motion of Saturn's rings"?

He was the only entrant to make enough headway to submit; Astronomer Royal George Airy called it one of the most remarkable applications of maths to physics he had seen.

Who was Katherine Mary Dewar, whom Maxwell married in Aberdeen on 2 June 1858?

Seven years his senior, she helped in his laboratory and worked on his viscosity experiments.

Why did Maxwell lose his Aberdeen professorship in 1860?

He then lost out to his friend Tait for the Edinburgh chair and went to King's College London instead.

Which near-fatal illness did Maxwell recover from in 1860 before moving to London?

His five years at King's College London were probably the most productive of his career.

What did Maxwell present at an 1861 Royal Institution lecture, photographed by Thomas Sutton?

The subject was a tartan ribbon shot through red, green and blue filters; the plates were barely sensitive to red, so the result was imperfect.

What was the subject of Maxwell and Sutton's pioneering 1861 colour photograph?

A 1961 study found the red exposure only worked because ultraviolet light leaked through the red filter.

Which Royal Society honour did Maxwell receive in 1860 for his work on colour?

He was elected a Fellow of the Society the following year.

Which older scientist did Maxwell regularly encounter at Royal Institution lectures?

The older man was 40 years his senior and showing signs of senility, but each respected the other's talents.

Maxwell's 1868 paper "On governors" is considered a founding document of which field?

The governors in question were the centrifugal devices that regulated the speed of steam engines.

What is the 1867 thought experiment in which an imaginary being sorts particles by energy called?

It appears to violate the second law of thermodynamics and still fuels debate about information and entropy.

Which physicist generalised Maxwell's gas-velocity theory, giving the distribution its double-barrelled name?

The formula gives the fraction of gas molecules moving at a given velocity at any temperature.

What did Maxwell construct in plaster in 1874 to explore phase transitions, based on Gibbs's papers?

A contemporary said only one man alive could understand Gibbs's papers: "That was Maxwell, and now he is dead."

Which chair did Maxwell become the first holder of when he returned to Cambridge in 1871?

He supervised every step of building the Cavendish Laboratory and buying its apparatus.

Whose unpublished research on Earth's density and the composition of water did Maxwell edit late in life?

The edition, with copious original notes, was one of his last great contributions.

Maxwell was the first to make explicit use of which method, in 1871, and helped establish the CGS system?

The CGS system, based on centimetres, grams and seconds, was the standard of physics for decades.

Which chaotic idea is Maxwell credited with first emphasising, in two 1870s discussions?

He recognised the significance of systems with "sensitive dependence on initial conditions" a century before chaos theory had a name.

From what did Maxwell die in Cambridge on 5 November 1879, aged 48?

His mother had died of the same disease at exactly the same age.

Where is Maxwell buried?

He does have a memorial inscription near the choir screen at Westminster Abbey.

Maxwell's best-known poem, Rigid Body Sings, is closely based on which Robert Burns song?

He reportedly sang it while accompanying himself on a guitar.

Which schoolfellow and lifelong friend wrote The Life of James Clerk Maxwell, published in 1882?

He also published a collection of Maxwell's poems the same year.

What did Einstein reply in 1922 when a Cambridge host said his greatness rested on Newton?

He also called Maxwell's work "the most profound and the most fruitful that physics has experienced since the time of Newton".

Where was Maxwell ranked in Physics World's survey of the 100 most prominent physicists?

A separate PhysicsWeb poll of rank-and-file physicists also placed him third.

On the Dynamical Theory of Gases (1867) introduced a model for which type of material?

The same paper originated the Maxwell–Cattaneo equation for heat transport in a medium.

What medium did Maxwell think light waves needed, later dismissed by Einstein as "superfluous"?

The Michelson–Morley experiment failed to detect it, and special relativity made it unnecessary.

What was the profession of Maxwell's father, John Clerk Maxwell of Middlebie?

He took the eleven-year-old to see Robert Davidson's demonstration of electric propulsion in 1842, an experience with profound implications.

Which lifelong friend, met at Edinburgh Academy, became a fellow physicist and later a rival to Kelvin's circle?

Meeting Tait and Lewis Campbell ended the isolation of the boy the other pupils had nicknamed 'Daftie'.

To which secret Cambridge debating society was Maxwell elected while at Trinity?

He had transferred from Peterhouse before the end of his first term, judging a Trinity fellowship easier to win.

In which year was Maxwell elected a Fellow of the Royal Society?

The election came a year after his Rumford Medal and in the same year as his two-part paper 'On Physical Lines of Force'.

Which office in the Church of Scotland did the devout Maxwell hold in his later years?

Raised on both Church of Scotland and Episcopalian services, he underwent an evangelical conversion in April 1853.

Which cousin, a civil engineer, served as Maxwell's best man at his wedding?

Another first cousin was the artist Jemima Blackburn, daughter of his father's sister.

How old was Maxwell's mother, roughly, when he was born?

His parents married in their thirties, and an earlier daughter, Elizabeth, had died in infancy.

Which paper of 1855, read to the Cambridge Philosophical Society, was Maxwell's first on electromagnetism?

It reduced the known laws to 20 equations in 20 variables, a simplified model of Faraday's ideas.

Maxwell used the newly developed linear algebra to prove whose trichromatic theory of colour vision?

His colour-matching experiments founded colourimetry and led directly to his colour photography.