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David Nightingale: James Clerk Maxwell (1831-1879)

James Clerk Maxwell
By Fergus of Greenock via Wikimedia Commons

Every moment of every day, worldwide, we all  realize one of the profound predictions of James Clerk Maxwell – which was that something called radio waves, traveling at the same speed as that of light, must exist.

There've been other profound predictions in science of course – for example, astronomer Le Verrier's prediction about where to find the planet Neptune.

But this little essay is about a man who was initially called 'Dafty' at school – born in Scotland in 1831, and who lived for only 48 years.

There are some glorious pen-and-ink sketches  shown in Crowther's excellent biography [ref.1]          including one of the little boy standing shyly behind protective grown-ups, observing a Fiddler at a Barn Dance, and yet another of the 10 yr old arriving at his aunt's house in Edinburgh in order to attend the new Edinburgh Academy.

His father was a small Scottish landowner, not far from Dumfries, and their little estate was called Glenlair. Although James' mother had died when he was only eight, the father was very supportive of all his son's schooling and learning.

But James was only called Dafty in that Edinburgh school briefly. At 14 he won his school's mathematical medal, as well as a prize for English verse, and at 16 entered Edinburgh University, transferring at 19 to Cambridge – where he was something of a social outcast because of his extreme Scottish accent and dialect, and his simple unstarched clothes.

Maxwell's earliest science interests came perhaps from nearer the age of 4  when he would demand “Show me how it doos” and “what's the go of that?”, and as a boy he had become very interested in the polarizing prisms of the Edinburgh scientist WmNicol – today's well-known 'Nicol prisms' that produce polarized light. From some home experiments he had even developed methods for tracing strains produced by pressure, in gelatine, (ibid., p.274) – which is actually an important method used in engineering design today.

However, at the age of 22, while studying hard for the highly competitive final exams at Cambridge, he became ill with 'brain fever' and so spent the summer recuperating at his father's home at Glenlair. He graduated at 23 – 2nd Wrangler – and then, awarded a Fellowship, turned his attention to electricity and magnetism.

Maxwell is usually thought of as a theorist, but while an undergraduate he was also experimentally making discs with sectors of 3 primary colors. These discs, when spun rapidly, can produce any color.

He was good-natured and shy. Based on Burns' “Comin' Through the Rye” he would sometimes sing to himself

                             Gin a body meet a body

                             Flyin' through the air.

                             Gin a body hit a body

                             Will it fly? And where?

Studying Saturn's rings, he proved that they could not be fluids, nor solid bodies – which would distort – but would have to be clouds of tiny satellite particles. This prediction was confirmed over 100 years later by the Voyager flybys.

After being a Cambridge Fellow for a couple of years he was appointed Professor of Physics at Aberdeen, and married the Principal's daughter, Katherine, who was some years older. Later, at 29, he was appointed to the Chair of Natural Philosophy at King's College, London, where he continued his researches in electricity as well as the kinetic theory of gases, all the while continuing the voluntary lectures for working men that he had begun in Scotland. In fact, his 5 years in London were perhaps his most productive. At home in Kensington, he also did experiments with his wife Katherine on the viscosity of gases.  Further, he gave up the ground floor of his house to his ill brother-in-law, (ibid., p.302), which made it necessary for him to have his meals in a very small back room, sometimes on his knees.

In his work on the unseen molecules of gases he calculated that the average speed of molecules of air was about 1,000 mph [actually 1505]  ft/sec] , and that each molecule made about 8.077 billion collisions per second (ibid., p.297)  – all of which is true.

Although after London he was appointed head of the new Cavendish lab in Cambridge, he was happiest in the long periods he was able to spend on his mini estate, Glenlair.

Finally, we said at the start that every day we use his results – yes, cell phones, radio and TV.  Sure enough, Maxwell's predicted waves were found a few years after his death, by Heinrich Hertz.


1. “Men of Science” by J.G.Crowther; W.W. Norton & Co, NY, 1936.
2.  Some biographical sources on the internet.    


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