1861: James Clerk Maxwell's greatest year
Posted on 18/04/2011
James Clerk Maxwell
James Clerk Maxwell (1831-79) was one of the world’s greatest physicists, and 2011 marks the 150th anniversary of two of his most important achievements, both accomplished while he was Professor of Natural Philosophy at King’s from 1860 to 1865. 1861 saw not only the publication of his first paper on electromagnetic theory, but also the first photograph produced according to Maxwell’s three-colour method, taken by photographic pioneer Thomas Sutton of King’s.
Born and brought up in Kirkcudbrightshire, south-western Scotland, Maxwell was educated at Edinburgh and Cambridge universities and then held the Chair of Natural Philosophy at Marischal College, Aberdeen, from 1856. His was one of a series of daring and inspired appointments of young scientists by King’s in the 19th century, also including Charles Lyell in geology, John Frederic Daniell in chemistry, Charles Wheatstone in physics and Joseph Lister in medicine. Stimulated by his contact with London scientific and intellectual life, Maxwell’s five years at King’s represent the most productive period of his career.
Through his four-part paper, beginning with ‘On Physical Lines of Force’, published in the Philosophical Magazine in 1861, Maxwell demonstrated that magnetism, electricity and light were different manifestations of the same fundamental laws. His 1865 paper, ‘A Dynamical Theory of the Electromagnetic Field’, published in the Philosophical Transactions of the Royal Society of London, described these, as well as radio waves, radar, and radiant heat, through a unique and elegant system of four partial differential equations, which paved the way for current technologies in radio, television, telephone and information exchange. ‘We have strong reason to conclude,’ Maxwell wrote in this paper, ‘that light itself - including radiant heat and other radiation, if any - is an electromagnetic disturbance in the form of waves propagated through the electro-magnetic field according to electro-magnetic laws.’
Albert Einstein, whose work on relativity and quantum theory was inspired by Maxwell’s discoveries, described how these equations produced a change in the conception of reality which was ‘the most profound and the most fruitful that physics had experienced since the time of Newton’. ‘One scientific epoch ended and another began with James Clerk Maxwell’, Einstein remarked.
Maxwell first suggested the three-colour method, which is the foundation of both chemical and electronic photographic processes, in a paper on ‘Experiments in Colour’, published in the Transactions of the Royal Society of Edinburgh in 1855, and in 1860 he won the Royal Society’s Rumford Medal for his work on colour and colour-blindness.
He realised that all the colours of nature can be counterfeited to the human eye by mixing red, green and blue in proportions which stimulate the three types of cells in the eye to the same degrees that the ‘real’ colours do. He suggested that if three colourless photographs of the same scene were taken through red, green and blue filters, and transparencies made from them were projected through the same filters and superimposed on a screen, the result would be an image reproducing all the colours in the original scene.
The first photograph made according to Maxwell’s suggestion was a set of three ‘colour separations’ of a tartan ribbon, created to illustrate an 1861 lecture given by Maxwell at the Royal Institution. These were taken and prepared by Thomas Sutton, lecturer on photography at King’s, inventor of the single-lens reflex camera, editor of Photographic Notes and compiler of the first English Dictionary of Photography.
King’s in fact was a early pioneer in the study of photography: Sutton’s predecessor from 1857 to 1860, Thomas Frederick Hardwich (author of A manual of photographic chemistry, theoretical and practical (1855) was Britain’s (and perhaps the world’s) first university professor in the subject, and King’s professors dominated the Photographic Society of the time. The great Charles Wheatstone, who invented the stereoscope and had a strong interest in vision and photography, was Vice-President, Hardwich was a Council member, and the Secretary was Philip Henry Delamotte, King’s Professor of Landscape Drawing and Perspective from 1855 and Professor of Fine Art from 1879, who photographed the building of the Crystal Palace at Sydenham.
In 1857 the Society’s journal reported that ‘a glass house, with a large commodious developing room, in connection with a chemical laboratory’ had been built at King’s that year. There is a collection of early photographs amassed by Wheatstone in the College Archives.
As Maxwell noted, the results of the three 1861 separations were imperfect because of the insensitivity of 1860s photographic materials to red and green light. Later researchers have demonstrated that the ‘red’ and ‘green’ images were in fact created by light from the blue-ultraviolet region of the spectrum which was not adequately blocked by the filters. Maxwell’s suggestion was not followed through to produce practical results until some 30 years later.
As well as developing his electromagnetic and colour theories, while he was at King’s Maxwell also extended his statistical theories on the nature of gases. He conducted experiments for the Electrical Standards Committee of the British Association for the Advancement of Science, and developed the standards for measuring electrical resistance, producing a report on ‘The Elementary Relations between Electrical Measurements’.
Besides lecturing, Maxwell gave weekly evening talks to artisans. Cyril Domb, former James Clerk Maxwell Professor at King’s, has demonstrated conclusively that there was no foundation to the rumour, published in FJC Hearnshaw’s 1928 history of the College, that Maxwell was asked to leave King’s because he could not keep order in his classes. Maxwell did, however, find he was short of time to pursue his scientific research, and in 1865 he left London and retired to his Scottish estate. In 1871 he was appointed the first Cavendish Professor of Natural & Experimental Philosophy at Cambridge.
Maxwell is commemorated at King’s in the building named after him at Waterloo; by the Clerk Maxwell Chair of Theoretical Physics (currently occupied by Professor John Ellis FRS) and by a plaque at the Strand Campus. The Maxwell Society organizes regular public lectures, and the College Archives hold some of his notebooks.
To commemorate Maxwell's achievements, there will be a series of lunchtime talks looking at colour from various viewpoints. For more information, please visit the Maxwell at King's website.