A historical interlude James Clerk Maxwell 18311879

James Clerk Maxwell spent his childhood at the family estate Glenlair in Galloway, in the Scottish lowlands. From the age of three he showed exceptional interest in how things work, and soon his parents had to answer endless questions on topics as diverse as the mechanism of a lock and the workings of the universe.

His mother was responsible for her son's early education and, under her guidance, James studied the basics of reading, writing and arithmetic, and learned and memorised passages from the Bible. By the time he was eight, she boasted that he could recite all 176 verses of the longest psalm in the Bible. This probably helped train his incredible memory; in later life he could recall information accumulated over long periods of time. This skill was apparent not only in his scientific work but also in his general knowledge on a whole range of topics. At one stage, between jobs, he was a professional memory-man in a circus.

James' mother did not live long enough to see her talented son develop. She died in 1839 and it now became more difficult to educate James at home. A tutor was employed, but this did not work out and John Maxwell had to send his son to the Edinburgh Academy. James arrived there on his first day wearing a tweed smock and square-toed shoes. With this unconventional dress and his slow, hesitant speech he was nicknamed Dafty. Used to a solitary existence, young Maxwell did not like the rough and tumble of the schoolyard and was essentially ostracised by the other pupils.

As the years passed Maxwell's ability and his extraordinary flair for mathematics became more and more apparent. When Maxwell was just fourteen, he completed his first scientific paper, 'On the Description of Oval Curves'.The method was original, the work probably inspired by unsuccessful attempts of a local artist to draw perfect ovals. His father showed it to John Forbes, the Professor of Natural Philosophy at the university, who had it published in the Proceedings of the Royal Society of Edinburgh.

After leaving school, Maxwell spent a year at Edinburgh University, where Philosophy was an integral part of the university course. The course put the emphasis on education rather than on cramming and there were no competitive examinations. His scientific training gave him the ability to approach problems with an open mind and without preconceptions, while Philosophy enabled him to peel away the superfluous parts of scientific theories, leaving only the essentials.

As a student, Maxwell had the privilege of being allowed to use Forbes' private laboratory during his undergraduate years and often assisted Forbes in experiments. He developed an interest in colour vision and was introduced to William Nicol (1768-1851) the inventor of the Nicol prism for polarisation of light. In typical fashion, young Maxwell built a crude polariser at home, did some experiments and sent watercolours of the results to Nicol, who presented him with a pair of Nicol prisms.

Maxwell moved to Cambridge in 1850. He brought a relaxed attitude towards the strict Cambridge traditions. When told that there would be compulsory church service at 6 a.m., his reaction was typical: 'Aye, I suppose I could stay up that late.' He spent one term at Peterhouse College and then moved to Trinity College, the largest and most liberal of the colleges.

After graduating he became a Fellow in 1855 and soon afterwards obtained a Professorship at Marischal College in Aberdeen. There he was responsible for the whole of the Natural Philosophy course. The preparation of demonstrations was one of his many duties. In one demonstration he would stand a student on a platform and 'pump him fu' o' electricity so his hair stood on end'. He allowed students to do their own experiments — a revolutionary innovation.

During his leisure time, Maxwell competed for and won the 1859 Adams Prize with an essay on the structure of Saturn's rings, in which he proved that they could not be gaseous but consisted of numerous small particles.

Maxwell was appointed Professor of Natural Philosophy at King's College, London, in 1860 and did much of his most important work on electromagnetism while he was there. He was very impressed by the work of Faraday, his ideas of 'lines of force' extending through space around interacting bodies. As I proceeded with the study of Faraday, I perceived that his method of conceiving the phenomena was also a mathematical one, although not exhibited in the conventional form or mathematical symbols'.

In 1864, Maxwell made a presentation to the Royal Society in London, and in 1865 he published his first paper, 'A Dynamical Theory of the Electromagnetic Field', in the Philosophical Transactions of the Royal Society. He concludes the paper with the following observation: 'We have strong reason to believe that light itself including radiant heat and other radiations, if any, is an electromagnetic disturbance in the form of waves propagated through the electromagnetic field.'

He left the college in 1865 and retreated to Glenlair. There he was free to do research and to rebuild the house as his father had intended.

Maxwell was persuaded out of retirement to become the first Cavendish Professor of Experimental Physics in 1871. He designed the famous Cavendish Laboratory, which opened in 1874. Maxwell's equations in the form we know them appeared in his book Electricity and Magnetism in 1873.

Maxwell was both a theorist and an experimentalist, an all-rounder brilliant enough to make fundamental contributions to many branches of physics. In addition to electromagnetism his name is linked with the kinetic theory of gases, colour vision, geometrical optics, and thermodynamics. Maxwell and T.H. Huxley were the scientific editors of the famous ninth edition of the Encyclopaedia Britannica.

Maxwell the philosopher had a great interest in the mechanics of the mind. In a letter to Campbell he wrote 'I believe there is a department of the mind conducted independent of consciousness, where things are fermented and decocted, so that when they are run off they become clear.'

Maxwell died in 1879. Just after his death, David Edward Hughes discovered, almost by accident, that sparks oscillating across a loose contact in an electrical circuit created electromagnetic signals which he could detect in another room of his house in Great Portland Street, London. Soon he was even able to detect them on the street outside, and became known as 'the mad professor wandering about listening to a box by his ear'. We now realise that he was experimenting with the first mobile telephone!

On 20 February 1880, Hughes demonstrated his equipment to members of the Royal Society, who, however, were quite sceptical. Edward Stokes (1819-1903) in particular suggested that the signals were produced by induction and not by electromagnetic waves, effectively dampening Hughes' enthusiasm, with the result that his idea was never published. The first experimental production of electromagnetic waves was recognised and credited to Heinrich Hertz in 1887.

An athlete clears the bar at the Olympic Games. Electromagnetic waves which came from the sun, and happen to be reflected in the right direction, cause electrons to jiggle in a television camera. Within a fraction of a second electrons in a hundred million television sets across the globe execute a similar jiggle. The waves which entered the camera from the athlete emerge from television screens in Europe, Asia, Africa, America and Australia. We do not even need wires connecting all these sets! All

David E. Hughes (1831-1900)

this is possible because the laws of Nature discovered by Maxwell have been applied in clever ways by men and women of science who followed him.

The discovery of the production and detection of electromagnetic waves has changed the history of mankind. 'Action and communicating at a distance', such as watching events on television, or directing and landing a spacecraft on a distant planet, have become commonplace. Maxwell's waves connect mobile phones, allow ships to 'see in the dark', guide aeroplanes safely to their destinations. At shorter wavelengths, X-rays penetrate matter and are used in medicine for both diagnostic and therapeutic purposes.

One can hardly express Maxwell's legacy better than in the words of Richard Feynman: 'From a very long view of the history of mankind — seen from, say, ten thousand years from now — there can be little doubt that the most significant event of the 19h century will be judged as Maxwell's discovery of the laws of electrodynamics. The American Civil War will fade into provincial insignificance in comparison with this important scientific event of the same decade'.

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