Lord Kelvin died on December 17, 1907, at Netherhall, in the house he had built some 30 years earlier. That year he had often appeared frailer and lamer to those who knew him well, and he had lost the sight in one eye, probably because of a detached retina. But at other times he was as lively as ever. At the British Association meeting in July at Leicester he had participated in a memorable discussion with Rutherford, Soddy, and others on radioactivity. His views were sharp but hard to fathom. At the 1904 BA meeting he had reportedly acknowledged that radioactive decay released energy locked up within the atom. But in March 1907, in one of his last published papers, he argued again for a sort of rechargeable atom, which took up energy from its surroundings then released it in a sudden burst of disintegration. “Lord Kelvin preferred to regard the atom as a big gun loaded with an explosive shell,” reported Nature from the BA. “The impossibility of the transmutation of one element into any other he declared to be almost absolutely certain.”
Even so, he expressed his opinions with vigor and with his old delight in argument. He had lost none of his simple joy in the enlightenment that only science could provide. After a lecture on recent progress in astronomy, he had spoken up to praise the speaker and his message.
“In proposing a vote of thanks,” one observer recalled, “Lord Kelvin burst into a sort of rhapsody, in which, with unaffected enthusiasm, he declared that we had been taken on a journey far more wonderful than that of Aladdin on the enchanted carpet; we had been carried to the remotest stars, and well-nigh round the Universe, and brought back safely to Leicester on the wings of science, and the most marvellous thing about it all was that it was true!”
From Leicester, Lord and Lady Kelvin went to the south of France for their habitual month of rest, but after the long journey home Lady Kelvin collapsed at Netherhall on September 15, apparently from a stroke. Kelvin stayed with her, as she began to improve. He himself stayed mostly well, but toward the end of November he caught a chill, took to his bed, seemed to be on the mend, but by the middle of December he relapsed and died quietly a few days later. He was 83.
Following memorial services at St. Columba’s Episcopal Church in Largs and at Glasgow University’s Bute Hall, Kelvin’s coffin went by train to London, arriving at Westminster Abbey on the morning of December 22. Lady Kelvin, still unwell, remained in Scotland. Kelvin’s funeral at Westminster on the 23rd, a dark, cold, midwinter day, manifested that combination of pomp and humility characteristic of high church Anglicanism. Distinguished scientists joined with representatives of the Crown and the government, foreign ambassadors, and other dignitaries. The Duchess of Argyll, a personal friend, was there; so was the First Lord of the Admiralty, and Kelvin’s old nautical ally Admiral Sir John Fisher. Scientific societies from around the world sent representatives, as did countless universities and scientific and technological associations from Great Britain and elsewhere. The pall bearers included Lord Rayleigh, the geologist Archibald Geikie, and George Darwin (Sir George by now), who had been Kelvin’s closest scientific confidante of the rising generation.
Into this solemn and magnificent assembly in Westminster Abbey Kelvin’s coffin was borne to the accompaniment of Purcell’s Music for Queen Mary and Chopin’s Funeral March. After the hymn “Brief Life Is Here Our Portion” came readings from Psalm 90 (“The days of our years are threescore years and ten; and if by reason of strength they be fourscore years, yet is their strength labour and sorrow; for it is soon cut off, and we
fly away”) and 1 Cor. xv (“O death, where is thy sting? O grave, where is thy victory?”).
Kelvin was interred beside Isaac Newton, beneath a plain slab inscribed “William Thomson, Lord Kelvin, 1824-1907.” As he was laid to rest the dean of the Abbey intoned the old words of the burial service, singularly inappropriate in this case: “Man that is born of woman hath but a short time to live, and is full of misery.”
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In writing about scientists of previous centuries and the mysteries they spent their lives trying to resolve, I have often wanted to speak back into the past, or bring these scientists forward to the present day, to show them how it all worked out. Of course, science solves one set of problems only to present new ones for the next generation, but I can’t help thinking that pioneers such as Faraday and Maxwell, Joule and Clausius, and especially such unrecognized explorers as Carnot would have been gratified to see how their difficult endeavors and half-perceived ideas laid the foundation for what we now understand.
In Kelvin’s case I am not so sure. His early thinking on thermodynamics and electromagnetism was profound and influential, yet as he grew old he grew unhappy with the developments that others, working from his clues, had pursued. J. J. Thomson recalled a conversation in which Kelvin said he thought the most valuable work of his career had been the long struggle to limit the ages of the earth and the sun. Few modern scientists would agree. The Baltimore lectures, representing the summation of Kelvin’s mechanical picture of the universe, now seem impossibly antique.
Obituary notices of Kelvin reflected this delicate judgment. In newspapers around the world he was “one of the greatest scientists and ablest men of the age,” “the foremost scientist of Great Britain,” and “the most distinguished British man of science.” His scientific prowess was noted, but the popular press mostly reminded readers of his contributions to electrical technology, especially in the Atlantic cable and its instrumentation. Such achievements characterized the astonishing transformation of the world by science and technology in the course of the 19th century, a transformation of which Kelvin was a prominent symbol. It was not for
science alone that Kelvin became famous but because of the way he brought science into ordinary life.
Scientific assessments of his life, on the other hand, emphasized his contributions to the understanding of energy and electromagnetism as the core of his legacy, along with his essential work in establishing scientific units for the new sciences, and a great deal of valuable investigation of fluid mechanics, elasticity of matter, and other more mundane but important works. Of his later scientific activity, S. P. Thompson observed in Nature, “it is less easy to speak.” The Baltimore lectures “remain a witness to his extraordinary fertility of intellectual resource,” while of his final ideas on radioactivity and “electrions,” Thompson carefully concluded, “it would be entirely premature to evaluate [their] ultimate importance.”
Also writing in Nature, Joseph Larmor described Kelvin as “a main pioneer and creator in the all-embracing science of energy, the greatest physical generalisation of the last century,” but conceded that even there “his fragmentary and often hurried writings on this subject” left to others the task of rationalizing the new ideas into rigorous and whole science. In a longer notice written for the Royal Society, Larmor’s reservations stood out more clearly still. Kelvin’s brilliance was not in doubt. “What a happy strenuous career his must have been…. New discoveries and new aspects of knowledge crowding in upon him faster than he could express them to the world…. In the first half of his life, fundamental results arrived in such volume as to leave behind all chance of effective development.” Kelvin had inspired Maxwell to start work on electromagnetism, Larmor noted, but Maxwell’s “genius was as systematic as Thomson’s was desultory.” There was the problem: Kelvin thought fast, so fast, in fact, that he never stopped to think.
And there was another misfortune: “One is at times almost tempted to wish that the electric cabling of the Atlantic … had never been undertaken by him.” Because after that his powers of original invention in science waned, and he channeled his admittedly enormous energy into too many distracting enterprises. A slightly silly story emphasizes the point. At Netherhall, Kelvin had been irked by a dripping tap. Naturally, he set out to design a better one, and his niece Agnes King told of happy hours running up and down stairs to turn the water on and off while her
uncle designed and experimented. He devised a valve and took out a patent. In 1894 Kelvin visited his niece at rented accommodations in London and, finding no one home, left his card. The landlord, seeing this, remarked, “Lord Kelvin is rather a clever man. He invented a watertap.” Delighted, his niece told the story later at a dinner party for Kelvin, and “everyone laughed except himself; he could not see the joke! … He was quite satisfied to be thought ‘rather clever,’ and wondered at our amusement.”
If family members were tickled at the thought of the great philosopher of nature being known for a piece of plumbing, scientists such as Larmor tut-tutted sadly. Kelvin was less of a physicist than he could have been, the thinking goes, because he dabbled in domestic engineering and other inconsequential matters. But laying aside the old snobbery that an intellectual cannot have practical talents, where is the truth in this? Kelvin was busy his entire life. Helmholtz, writing to his wife after a visit, at first thought that “Sir Wm might do better than apply his eminent sagacity to industrial undertaking” but quickly changed his mind: “I did Thomson an injustice in supposing him to be wholly immersed in technical work; he was full of speculations as to the original properties of bodies, some of which were very difficult to follow; and as you know he will not stop for meals or any other consideration.”
When he was inventing his tap and refining his compass, in other words, Kelvin was also working up his Baltimore lectures, elaborating his vortex models of atom and ether, corresponding with FitzGerald on electromagnetism, and so on. If he had not invented the tap, would he somehow have been led to change his mind about Maxwell’s theory? Of course not. The fact that he pursued an intellectual course largely alone, long after everyone else had abandoned it, and which turned out to be a historical dead end, has nothing to do with his skills of practical invention.
Kelvin clung to his outdated view of a strictly mechanical universe because he sincerely believed it was the right line to take. In his last years he must have been dismayed that he would not live to see how all the confusing questions thrown up at the beginning of the new century would turn out. Would he, brought back a century later, react to the modern physicists’ view of the world with amazement or horror? It is easy to imagine that quantum mechanics would have befuddled and further
dismayed him, since it took away forever the elementary picture of absolute cause and effect, of microphysics that could be interpreted as mechanical systems writ small.
But then I wonder. As much as he stuck to his established conceptions, Kelvin was capable of abandoning ideas with little regret when it was clear they would not do. By the end of his life he had discarded his old faith in vortex atoms and acknowledged that not one of his ether models was adequate. He did not know what would come in their place, but as he and others said, he needed a model in order to understand a theory. Quantum mechanics, in its pure form, might well have seemed elusive to him, but surely he would have loved particle physics. The giant machines, a mile or more around, accelerating tiny fragments of matter and smashing them into each other to see what smaller fragments would fly out—this is a science Kelvin could embrace. The strange subatomic forces that keep quarks bundled up inside atomic nuclei: This is Kelvin’s physics! It’s Boscovich! It’s Aepinus Atomized! Elementary particles as constructions of tiny ingredients held together by peculiar but necessary forces—Kelvin would have convinced himself, I am sure, that this was exactly the kind of thing he had in mind when he was preaching against the nihilism of the Maxwellians and their mathematically austere electric and magnetic fields.
Even the vacuum, according to modern physics, is not a void but a seething medium of virtual particles coming and going. Electromagnetic fields, likewise, are portrayed now not as continuous entities, elastic but abstract, pervading space, but as the manifestation of forces transmitted by quantum particles, specifically photons. Many physicists today who probe the universe at its most fundamental level of construction speak of superstrings and their offspring, lines and loops wiggling around in multidimensional spaces and creating for us, in our limited three-dimensional world, the appearance of point particles and continuous forces. It is (as S. P. Thompson said of Kelvin’s late thinking) entirely premature to judge whether superstrings and their ramifications will serve as the foundation of a final theory of physics, or lead the way to some other as yet unconceived theory, or, like the vortex atom and the sponge ether, go the way of the dinosaurs. But I think Kelvin, with his ability to dream up
endlessly ingenious pictures based on elementary principles and his fondness for adding mathematical complication to explain hard empirical phenomena, would after being taken aback by the dizzying scope of modern theoretical physics decide that, after all, it was exactly what he had been trying to say.