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Lord Kelvin

Scientist and inventor: ‘He may be said to have taken all

physical science to be his province’

17 December 1907

We deeply regret to announce the death of the most distinguished British man of science, Lord Kelvin, which took place last night, at his Scottish residence, Netherhall, Largs. Lord Kelvin had not been well for over three weeks. He caught a chill on November 23, and his condition became serious some days ago.

William Thomson, Baron Kelvin of Largs, was born in Belfast on June 24, 1824. The second son of James Thomson, a remarkable man who, though he started with very slender advantages of education, died in 1849 Professor of Mathematics in the University of Glasgow, he began to attend the classes at Glasgow at the age of 11, and in the year he attained his majority graduated from Peterhouse, Cambridge, as Second Wrangler and first Smith’s Prizeman. His success immediately earned him a Fellowship at his college, and in the following year, after spending a short time in Regnault’s Laboratory in Paris, he returned to succeed Dr. Meikleham in the Chair of Natural Philosophy at Glasgow.

It is not often that a father and son simultaneously hold professorships at an important University; but even that does not exhaust the academic record of the Thomson family. Lord Kelvin’s elder brother James was Professor of Engineering in the University from 1873 to 1889, so that three professors at Glasgow were provided by two generations of the descendants of a small farmer in the north of Ireland. The rest of Lord Kelvin’s life is chiefly a record of strenuous and successful scientific work which obtained early recognition.

The Royal Society made him one of their number in 1851, and, after conferring on him successively a Royal and a Copley medal, accorded him in 1890 the highest honour at their disposal by choosing him to be their president. At the British Association, of which he acted as president at Edinburgh in 1871, he was an assiduous attendant. Much of his work was first published as communications or reports to that body, and it was only at its last meeting that he delivered a long address on the constitution of matters and the electronic theory. Honorary degrees he received in abundance, among them being D. C. L. from Oxford and LL. D. from Cambridge, Dublin, and Edinburgh, together with many foreign academical distinctions.

In 1896 he was knighted for the part he took in the laying of the Atlantic cable, and when, in 1892, Lord Salisbury created him a peer he borrowed his title from the stream that flows below the University in which his scientific life had been spent. He received the Order of Merit on its institution in 1902 – he was already a member of the Prussian Order ‘Pour le Mérite’ – and in the same year became a Privy Councillor. But perhaps the crowning occasion of his life was the celebration of his jubilee as professor at Glasgow in 1896, when a unique gathering assembled to do him honour, and congratulations from scientific men in all quarters of the globe testified to the universal admiration with which his genius was regarded.

Three years later, after 53 years’ service, he resigned his Glasgow professorship. But his retirement by no means meant the cessation of active work. While still maintaining his connexion with the University, of which in 1904 he was unanimously chosen Chancellor in succession to the Earl of Stair, he continued to contribute to the proceedings of various scientific societies, and much of his time was devoted to the rewriting and revision of his Baltimore lectures on molecular dynamics and the wave theory of light.

These lectures were delivered at Johns Hopkins University in 1884, and the printing of them, begun in 1885, was only brought to a conclusion in 1904. He chose the wave-theory as his subject with the deliberate intention of accentuating its failures, but in his preface to the volume published in 1904 he was able to express his satisfaction that it contained a dynamical explanation of every one of the difficulties which had been encountered in the lectures 20 years before. Lord Kelvin was also a director of several manufacturing companies, and his name formed part of the style of the Glasgow firm which manufactures his compass and measuring instruments. He was president of the institution of Electrical Engineers for the present year, though he did not live to deliver his inaugural address.

Within the limits of a short article it is impossible to give a full account of Lord Kelvin’s achievements in the realms of scientific thought and discovery. Generally recognised at the time of his death as the foremost living physicist, he was not less remarkable for the profundity of his researches than for the range and variety of his attainments. Not confining himself to a single more or less specialised department of learning, he may be said to have taken all physical science to be his province; for there were few branches of physical inquiry that he did not touch, and all that he touched he adorned. Perhaps this many sidedness of his intellectual interests may be connected with the deep conviction he cherished of the unity of all Science, and his impatience of conclusions which, drawn from a limited field of study, were in opposition to the well-ascertained facts of wider generalisations.

On one occasion, when accused of being ‘hard on the geologists,’ he repudiated the suggestion with the remark that he did not believe in one science for the mathematician, another for the chemist, another for the physicist, and another for the geologist. All science, he said, is one science, and any part of science that places itself outside the pale of the other sciences ceases for the time being to be a science.

Some idea may be obtained of the amount of his scientific work from the fact that, according to the Royal Society’s Catalogue of Scientific Papers, down to the year 1883 he had published 262 memoirs under his name, not including papers published jointly with other men; while his republished mathematical papers – not yet completed – already fill three substantial volumes. Nor must his contributions to the increase of natural knowledge – to use one of his favourite expressions – be reckoned merely by the sum of the results at which he was personally able to arrive.

Hundreds of men are proud to recognise him as their master, and in all parts of the world scientific workers may be found who have not only profited by his advice and been stimulated by his enthusiasm, but owe to him in many cases the very subjects of research upon which they are engaged – either as his direct suggestions or as problems opened out by his prior investigations.

To solve the puzzle of the ultimate constitution of matter may be regarded as the goal of the pure physicist’s ambition. The problem afforded Lord Kelvin a congenial field of speculation, and he succeeded in propounding an hypothesis as to the nature of atoms which, according to Clerk Maxwell, satisfied more of the conditions than any hitherto imagined. Starting from a number of mathematical theorems established by Helmholtz respecting the motion of a perfect, incompressible fluid, he suggested that the universe may be filled with such a primitive fluid of which in itself we can know nothing, but of which portions become apparent to our perceptions as matter when converted by a particular mode of motion into vortex-rings. These vortex-rings (of which a fair imitation is given by smoke rings in air) are the atoms or molecules that compose all material substances. They are indivisible not because of their hardness and solidity, but because they are permanent both in volume and in strength. Lord Kelvin’s work on the atomic theory, though perhaps his most striking contribution to mathematical physics, is only a small part of the whole. Light, electricity, and magnetism, to mention a few wide departments, all engaged his attention, to what extent may be judged from the fact that his papers on electrostatics and magnetism alone up to 1872 filled a volume of 600 pages.

Some of the earliest and not least important of Lord Kelvin’s work was in connection with the theory of heat: indeed he is to be looked upon as one of the founders of the modern science of thermodynamics. In 1824 Sadi Carnot published his book on the motive power of heat, setting forth the conditions under which heat is available in a heat-engine for the production of mechanical work, but it attracted little or no attention until Lord Kelvin about the middle of the century drew the notice of the scientific world to its value and importance.

A direct and immediate result of Lord Kelvin’s study of Carnot’s work was his definition of the ‘Absolute scale of temperature’ – that is, a scale which, unlike the graduations of an ordinary thermometer that are based on the observed alterations in volume produced in a particular material by heat or cold, is independent of the physical properties of any specific substance. A second addition to science soon followed in the principle of the dissipation of energy, enunciated in 1852. A further general inference is that this earth, as now constituted, has been within a finite time, and within a finite time will again become unfit for human habitation.

In a paper communicated to the Royal Society of Edinburgh in 1862 he declared that for 18 years it had been pressed on his mind that much current geological speculation was at variance with essential principles of thermodynamics, and proceeded to show from considerations founded on the conduction of heat that the earth must within a limited time have been too hot for the existence of life. Six years later, in an address on ‘Geological Time’ which provoked a lively controversy with Huxley, he brought some other physical considerations to bear on the question.

Since the tides exercise a retarding influence on the rotation of the earth, it must in the past have been revolving more quickly than it does now, and calculations of its deceleration indicate that within the periods of time required by some geologists it must have been going at such a speed that it could not have solidified into its present shape. But Lord Kelvin did not think the amount of centrifugal force existing 100 million years ago incompatible with its present form. Again he pointed out that the sun cannot be regarded as a permanent and eternal factor in the universe.

It is only fair, however, to say that his arguments have not been universally endorsed even among physicists; and it has been urged that there are other assumptions – in regard, for instance, to the conductivity of the earth’s interior – not less admissible than those adopted by him, which lead to results much more favourable to the geological and biological demand for more time. Radium, too, has been invoked to explain the maintenance of the sun’s heat.

Great as were Lord Kelvin’s achievements in the domains of scientific speculation, his services to applied science were even greater. A prolific and successful inventor, he had nothing in common with that frequent class of patentees who are brimming over with ideas, all crude, most worthless, and only in occasional instances capable of being worked up into something valuable by men combining the requisite mechanical skill with an adequate knowledge of scientific first principles. Invention with him was not a mere blind groping in the dark, but a reasoned process leading to a definitely conceived end.

Of the scores of patents he took out few have not been found of practical and commercial value. It was in connection with submarine telegraphy that some of his most valuable inventions were produced in this department, indeed, his work was of capital importance and of itself sufficient to establish his title to lasting fame. Lord Kelvin was a firm believer in the practicability of transoceanic telegraphy and did not hesitate to show by acts the faith that was in him. He became a director of the Atlantic Telegraph Company, which hazarded large sums in the enterprise of making and laying a cable, and he took an active and personal part in the operations which culminated in the successful laying of the short-lived cable of 1853.

As is well known, the system broke down completely after it had been in use for a very short time, and there is little reason to doubt that the reason of its untimely end was the inability of its insulation to stand the potentials to which it was exposed. Lord Kelvin, who believed that but for this treatment the cable would have worked satisfactorily, declared that feeble currents ought to be employed together with very sensitive receiving instruments, and, characteristically, was ready, not only with a theoretical prescription, but with the working instrument, his mirror galvanometer, that enabled it to be carried into effect.

Some of his finest work is to be found in his electric measuring instruments, a subject in which his knowledge and authority were unrivalled. More especially was this the case in regard to electrostatic measurements – perhaps the most difficult of all. When the need for accurate instruments in his studies on atmospheric electricity caused him to take up the matter, the electrometers in existence were little more than electroscopes – capable of indicating a difference of electric potential, but not of measuring it; but in his quadrant, portable, and absolute electrometers his skill and ingenuity put at the disposal of electricians three beautiful instruments of exact research.

Measurement he regarded as the beginning of science and as the origin of many of the grandest discoveries. Hence he was always ready to do anything by which it could be facilitated, whether in matters of daily life or abstruse scientific inquiry. Thus on the one hand the metric system found in him a strong supporter, and he rarely missed a chance of bestowing a word or two of half-humorous disparagement upon the unhappy English inch or ‘that most meaningless of modern measures, the British statute mile.’

A keen amateur yachtsman, he developed navigational aids for ships, a steady compass that could still work accurately when a ship rolls at sea, and a sounding mechanism to measure depth at regular intervals.

As a lecturer Lord Kelvin was rather prone to let his subject run away with him. When this happened, limits of time became of small account, and his audience, understanding but little of what he was saying, were fain to content themselves with admiring the restless vivacity of his manner (which was rather emphasised than otherwise by the slight lameness from which he suffered) and the keen zest with which he revelled in the intricacies of the matter in hand. Similarly, the intelligence and patience of his Glasgow classes were not always equal to the mental strain entailed by his expositions, and, though they were thoroughly proud of him and his attainments, their orderliness was not of the strictest kind, and they were not above varying the proceedings with an occasional practical joke. But he was quick to express his approval of a piece of good work, or his delight at a new result or well-planned experiment; and no one could come in contact with him without feeling the charm of his kindly, lovable nature, and falling under the spell of the enthusiasm and untiring energy with which he devoted himself to the advancement of knowledge.

Lord Kelvin was twice married; first, to Margaret, daughter of Mr. Walter Crum, of Thornliebank; and, secondly to Frances Anna, daughter of Mr. Charles R. Blundy, of Madeira. There was no issue of either marriage.

A devout Christian, Kelvin believed that his theory of heat-death and his calculations of the age of the earth exposed flaws in Charles Darwin’s idea of evolution. To some Victorians, however, the implications of his ideas about the finite habitability of the earth seemed to offer a doom-laden vision of an icy end to all things rather than a fiery one.