Dafty - the forgotten physicist

Graham Farmelo salutes the genius behind the theory of electromagnetism.

The great physicist James Clerk Maxwell gratefully reflected on his deathbed that life had treated him gently. Alas, this treatment did not extend to posterity, which has been cruelly unjust.

In the pantheon of physicists, Maxwell stands alongside Galileo, Newton and Einstein. Of these, Maxwell is the only one who is virtually unknown outside science. The Galloway Gazette , the local paper of the region in which Maxwell was born and raised, failed last year to include him among its candidates in a poll to identify the most distinguished Gallovidian of all time. Scientists have not always been vigilant of his memory either: when the Queen spoke at the Royal Society's tricentennial celebrations in 1960, she listed some of its most distinguished former fellows but failed to include Maxwell.

Shortly after Her Majesty's oversight, the American physicist Richard Feynman showed that he appreciated Maxwell's worth better than his British colleagues. He wrote: "From the long view of this history of mankind - seen from, say, 10,000 years from now - there can be little doubt that the most significant event of the 19th century will be judged as Maxwell's discovery of the laws of electromagnetism."

Maxwell's unified theory of electricity and magnetism gave the theoretical underpinning for the electrical and telecommunications revolutions, and was the first example of a field theory, now universally regarded as the correct way of setting out a fundamental theory of the particles of matter and their interactions. If these were his only contributions to science, he would be regarded as one of the finest-ever physicists. Yet he did much more: he set out the statistical theory of the motion of gas particles, did important work in the theory of heat and invented a powerful method for calculating the forces in any mechanical structure. He was an accomplished experimenter, produced the first colour photograph and founded the Cavendish Laboratory in Cambridge, one of the most productive laboratories in the entire history of science.

Basil Mahon, a retired engineer, wrote this biography to tell the story of Maxwell's life and achievements to a wide audience and to win him "a little of the public recognition he so clearly deserves". The story Mahon tells is full of incident. Maxwell was born in 1831 into a wealthy family. He was not an especially bright student (he was nicknamed "dafty") but was strikingly inquisitive about the way things work; "What's the go o' that?"

he would ask. After winning his degree at Cambridge (where he was second wrangler), he embarked on an academic career. He was turned down by the University of Edinburgh for its chair in natural philosophy after being made redundant from Marischal College in Aberdeen. It was in his Scottish retreat that he brilliantly predicted the existence of electromagnetic waves, but before he could show that they were waves of light he had to wait weeks to look up the appropriate data in a library at King's College London. He died of stomach cancer, aged 48, before his theory of electromagnetism was experimentally verified and accepted by his peers.

Sadly, Mahon makes little of his potentially exciting material. He draws heavily on earlier biographies of Maxwell, notably the 1882 one by Maxwell's colleagues Lewis Campbell and William Garnett, but seems to ignore recent scholarship that would have given his book much-needed colour and depth. For example, I can see scant evidence that Mahon has consulted the recently published edition of Maxwell's extant scientific correspondence and manuscripts. One especially egregious fault of this biography is its failure to illuminate the role of the "Maxwellians", the physicists who did so much in the late 19th century to promote the importance of Maxwell's work. The crucial contribution of the wonderfully eccentric Oliver Heaviside is relegated by Mahon to a footnote. Yet it was Heaviside who first took Maxwell's original, somewhat cumbersome set of 20 equations of electromagnetism and condensed them into the four equations that every physics student now studies.

Apart from some gentle criticism of Maxwell's somewhat wayward style of lecturing, Mahon scarcely musters an uncomplimentary word about his hero, whom he describes as "not only a consummate scientist but a man of extraordinary personal charm and generous spirit". Maxwell may well be deserving of this praise, but his memory is not well served by writing his life as a hagiography.

Maxwell deserves much better than this well-intentioned but deeply dull book. Let us hope other biographers will more successfully take up the challenge of righting the wrongs of posterity's cruelty. There is every hope of success: when the Galloway newspaper realised its error in failing to include Maxwell in its list of candidates, it corrected its mistake and described to its readers his achievements and legacy. When the votes were counted, Maxwell came top. The runner-up was Saint Ninian.

Graham Farmelo is senior research fellow at the Science Museum, London.