William Thomson, 1st Baron Kelvin
William Thomson, 1st Baron Kelvin,
GCVO,
OM,
PC,
PRS FRSE (
26 June,
1824 –
17 December,
1907) was an
Irish-
Scottish mathematical physicist,
engineer, and outstanding leader in the
physical sciences of the
19th century. He did important work in the
mathematical analysis of
electricity and
thermodynamics, and did much to unify the emerging discipline of
physics in its modern form.
He also enjoyed a second career as a
telegraph engineer and
inventor, a career that propelled him into the public eye and ensured his wealth, fame and honour.
Family
William's father was Dr. James Thomson, the son of a
Belfast farmer. James received little youthful instruction in
Northern Ireland but, when 24 years old, started to study for half the year at the
University of Glasgow,
Scotland, while working as a
teacher back in Belfast for the other half. On graduating, he became a
mathematics teacher at the
Royal Belfast Academical Institution. He married Margaret Gardner in
1817 and, of their children, four boys and two girls survived infancy.
William, and his elder brother
James, were tutored at home by their father while the younger boys were tutored by their elder sisters. James was intended to benefit from the major share of his father's encouragement, affection and financial support and was prepared for a fashionable career in
engineering. However, James was a sickly youth and proved unsuited to a sequence of failed
apprenticeships. William soon became his father's favorite.
In
1832, the father was appointed professor of mathematics at
Glasgow and the family relocated there in October
1833. The Thomson children were introduced to a broader cosmopolitan experience than their father's rural upbringing, spending the summer of
1839 in
London and, the boys, being tutored in
French in
Paris. The summer of
1840 was spent in
Germany and the
Netherlands. Language study was given a high priority.
Youth
William began study at Glasgow University in
1834 at the age of 10, not out of any precociousness; the University provided many of the facilities of an elementary school for abler pupils and this was a typical starting age. In
1839,
John Pringle Nichol, the professor of
astronomy, took the chair of
natural philosophy. Nichol updated the curriculum, introducing the new mathematical works of
Jean Baptiste Joseph Fourier. The mathematical treatment much impressed Thomson.
In the academic year 1839-
1840, Thomson won the class prize in
astronomy for his
Essay on the figure of the Earth which showed an early facility for mathematical analysis and creativity. Throughout his life, he would work on the problems raised in the essay as a
coping strategy at times of personal
stress.
Thomson became intrigued with Fourier's
Théorie analytique de la chaleur and committed himself to study the "Continental" mathematics resisted by a
British establishment still working in the shadow of Sir
Isaac Newton. Unsurprisingly, Fourier's work had been attacked by domestic mathematicians,
Philip Kelland authoring a critical book. The book motivated Thomson to write his first published
scientific paper[P.Q.R (1841) "On Fourier's expansions of functions in trigonometric series" Cambridge Mathematical Journal 2, 258-259] under the
pseudonym P.Q.R., defending Fourier, and submitted to the
Cambridge Mathematical Journal by his father. A second P.Q.R paper followed almost immediately
[P.Q.R (1841) "Note on a passage in Fourier's 'Heat'" Cambridge Mathematical Journal 3, 25-27].
While vacationing with his family in
Lamlash in 1841, he wrote a third, more substantial, P.Q.R. paper
On the uniform motion of heat in homogeneous solid bodies, and its connection with the mathematical theory of electricity.
[P.Q.R (1842) "On the uniform motion of heat and its connection with the mathematical theory of electricity" Cambridge Mathematical Journal 3, 71-84] In the paper he made remarkable connections between the mathematical theories of
heat conduction and
electrostatics, an
analogy that
James Clerk Maxwell was ultimately to describe as one of the most valuable
science-forming ideas.[, Vol.2, p.301]Cambridge
William's father was able to make a generous provision for his favourite son's education and, in
1841, installed him, with extensive letters of introduction and ample accommodation, at
Peterhouse, Cambridge. In
1845 Thomson graduated as second
wrangler. However, he won a
Smith's Prize, sometimes regarded as a better test of originality than the
tripos.
Robert Leslie Ellis, one of the examiners, is said to have declared to another examiner
You and I are just about fit to mend his pens.[Thompson (1910) vol.1, p.98]While at Cambridge, Thomson was active in sports and athletics. He won the Silver Sculls, and rowed in the winning boat of the
Oxford and Cambridge Boat Race. He also took a lively interest in the classics, music, and literature; but the real love of his intellectual life was the pursuit of science. The study of
mathematics, physics, and in particular, of
electricity, had captivated his imagination.
In 1845 he gave the first mathematical development of
Faraday's idea that electric induction takes place through an intervening medium, or "dielectric", and not by some incomprehensible "action at a distance". He also devised a hypothesis of electrical images, which became a powerful agent in solving problems of electrostatics, or the science which deals with the forces of electricity at rest. It was partly in response to his encouragement that Faraday undertook the research in September of 1845 that led to the discovery of the
Faraday effect, which established that light and magnetic (and thus electric) phenomena were related.
On gaining a fellowship at his college, he spent some time in the laboratory of the celebrated
Henri Victor Regnault, at
Paris; but in 1846 he was appointed to the chair of natural
philosophy in the University of Glasgow. At twenty-two he found himself wearing the gown of a learned professor in one of the oldest Universities in the country, and lecturing to the class of which he was a freshman but a few years before.
Thermodynamics
By
1847, Thomson had already gained a reputation as a precocious and maverick scientist when he attended the
British Association for the Advancement of Science annual meeting in
Oxford. At that meeting, he heard
James Prescott Joule making yet another of his, so far, ineffective attempts to discredit the
caloric theory of
heat and the theory of the
heat engine built upon it by
Sadi Carnot and
Émile Clapeyron. Joule argued for the mutual convertibility of heat and
mechanical work and for their mechanical equivalence.
Thomson was intrigued but skeptical. Though he felt that Joule's results demanded theoretical explanation, he retreated into an even deeper commitment to the Carnot-Clapeyron school. He predicted that the
melting point of
ice must fall with
pressure, otherwise its expansion on freezing could be exploited in a
perpetuum mobile. Experimental confirmation in his laboratory did much to bolster his beliefs.
In
1848, he extended the Carnot-Clapeyron theory still further through his dissatisfaction that the
gas thermometer provided only an
operational definition of temperature. He proposed an
absolute temperature scale[Chang (2004), Ch.4] in which
a unit of heat descending from a body A at the temperature T
° of this scale, to a body B at the temperature (T
-1)°, would give out the same mechanical effect [work]
, whatever be the number T
. Such a scale would be
quite independent of the physical properties of any specific substance.[Thomson, W. (1848) "On an absolute thermometric scale founded on Carnot's theory of the motive power of heat, and calculated from Regnault's observations" Math. and Phys. Papers vol.1, pp100-106] By employing such a "waterfall", Thomson postulated that a point would be reached at which no further heat (caloric) could be transferred, the point of
absolute zero about which
Guillaume Amontons had speculated in
1702. Thomson used data published by Regnault to
calibrate his scale against established measurements.
In his publication, Thomson wrote:
- but a footnote signaled his first doubts about the caloric theory, referring to Joule's
very remarkable discoveries. Surprisingly, Thomson did not send Joule a copy of his paper but when Joule eventually read it he wrote to Thomson on
October 6, claiming that his studies had demonstrated conversion of heat into work but that he was planning further experiments. Thomson replied on the 27th, revealing that he was planning his own experiments and hoping for a reconciliation of their two views.
Thomson returned to
critique Carnot's original publication and read his analysis to the
Royal Society of Edinburgh in January
1849[- (1949) "An account of Carnot's theory of the motive power of heat; with numerical results deduced from Regnault's experiments on steam" Math. and Phys. Papers vol.1, pp113-1154], still convinced that the theory was fundamentally sound. However, though Thomson conducted no new experiments, over the next two years he became increasingly dissatisfied with Carnot's theory and convinced of Joule's. In February
1851 he sat down to articulate his new thinking. However, he was uncertain of how to frame his theory and the paper went through several drafts before he settled on an attempt to reconcile Carnot and Joule. During his rewriting, he seems to have considered ideas that would subsequently give rise to the
second law of thermodynamics. In Carnot's theory, lost heat was
absolutely lost but Thomson contended that it was
"lost to man irrecoverably; but not lost in the material world". Moreover, his
theological beliefs led to speculation about the
heat death of the universe.
Compensation would require
a creative act or an act possessing similar power.
In final publication, Thomson retreated from a radical departure and declared "the whole theory of the motive power of heat is founded on ... two ... propositions, due respectively to Joule, and to Carnot and Clausius."
[Thomson, W. (1851) "On the dynamical theory of heat; with numerical results deduced from Mr. Joule's equivalent of a thermal unit and M. Regnault's observations on steam" Math. and Phys. Papers vol.1, pp175-183] Thomson went on to state a form of the second law:
In the paper, Thomson supported the theory that heat was a form of motion but admitted that he had been influenced only by the thought of Sir
Humphry Davy and the experiments of Joule and
Julius Robert von Mayer, maintaining that experimental demonstration of the conversion of heat into work was still outstanding.
[Ibid p.183]As soon as Joule read the paper he wrote to Thomson with his comments and questions. Thus began a fruitful, though largely epistolary, collaboration between the two men, Joule conducting experiments, Thomson analyzing the results and suggesting further experiments. The collaboration lasted from
1852 to
1856, its discoveries including the
Joule-Thomson effect, and the published results
[Thomson, W. (1856) "On the thermal effects of fluids in motion" Math. and Phys. Papers vol.1, pp333-455] did much to bring about general acceptance of Joule's work and the
kinetic theory.
 |
A photograph of Thomson, likely from the late-19th century. |
Calculations on data-rate
Though now eminent in the academic field, Thomson was obscure to the general public. In September
1852, he married childhood sweetheart Margaret Crum but her health broke down on their
honeymoon and, over the next seventeen years, Thomson was distracted by her suffering. On
October 16,
1854,
George Gabriel Stokes wrote to Thomson to try to re-interest him in work by asking his opinion on some experiments of
Michael Faraday on the proposed
transatlantic telegraph cable.
To understand the technical issues in which Thomson became involved, see Submarine communications cable: Bandwidth problemsFaraday had demonstrated how the construction of a cable would limit the rate at which messages could be sent — in modern terms, the
bandwidth. Thomson jumped at the problem and published his response that month
[- (1854) "On the theory of the electric telegraph" Math. and Phys. Papers vol.2, p.61]. He expressed his results in terms of the
data rate that could be achieved and the
economic consequences in terms of the potential
revenue of the transatlantic undertaking. In a further
1855 analysis
[- (1855) "On the peristaltic induction of electric currents in submarine telegraph wires" Math. and Phys. Papers vol.2, p.87], Thomson stressed the impact that the design of the cable would have on its
profitability.
Thomson contended that the speed of a signal through a given core was inversely proportional to the
square of the
length of the core. Thomson's results were disputed at a meeting of the British Association in
1856 by
Wildman Whitehouse, the
electrician of the
Atlantic Telegraph Company. Whitehouse had possibly misinterpreted the results of his own experiments but was doubtless feeling financial pressure as plans for the cable were already well underway. He believed that Thomson's calculations implied that the cable must be "abandoned as being practically and commercially impossible."
Thomson attacked Whitehouse's contention in a letter to the popular
Athenaeum magazine
[- (1855) "Letters on telegraph to America" Math. and Phys. Papers vol.2, p.92], pitching himself into the public eye. Thomson recommended a larger
conductor with a larger
cross section of
insulation. However, he thought Whitehouse no fool and suspected that he may have the practical skill to make the existing design work. Thomson's work had, however, caught the eye of the project's undertakers and in December
1856, he was elected to the
board of directors of the Atlantic Telegraph Company.
Scientist to engineer
Thomson became scientific adviser to a team with Whitehouse as chief electrician and Sir
Charles Tilston Bright as chief engineer but Whitehouse had his way with the
specification, supported by Faraday and
Samuel F. B. Morse.
Thomson sailed on board the cable-laying ship
HMSS Agamemnon in August
1857, with Whitehouse confined to land owing to illness, but the voyage ended after just 380
miles when the cable parted. Thomson contributed to the effort by publishing in the
Engineer the whole theory of the
stresses involved in the laying of a submarine
cable, and showed that when the line is running out of the ship, at a constant speed, in a uniform depth of water, it sinks in a slant or straight incline from the point where it enters the water to that where it touches the bottom
[- (1857) Math. and Phys. Papers vol.2, p.154].
Thomson developed a complete system for operating a submarine telegraph that was capable of sending a
character every 3.5
seconds. He
patented the key elements of his system, the
mirror galvanometer and the
siphon recorder, in
1858.
However, Whitehouse still felt able to ignore Thomson's many suggestions and proposals. It was not until Thomson convinced the board that using a purer
copper for replacing the lost section of cable would improve data capacity, that he first made a difference to the execution of the project
[Sharlin (1979) p.141].
The board insisted that Thomson join the 1858 cable-laying expedition, without any financial compensation, and take an active part in the project. In return, Thomson secured a trial for his mirror galvanometer, about which the board had been unenthusiastic, alongside Whitehouse's equipment. However, Thomson found the access he was given unsatisfactory and the
Agamemnon had to return home following the disastrous
storm of June 1858. Back in London, the board was on the point of abandoning the project and mitigating their losses by selling the cable. Thomson,
Cyrus Field and
Curtis M. Lampson argued for another attempt and prevailed, Thomson insisting that the technical problems were tractable. Though employed in an advisory capacity, Thomson had, during the voyages, developed real engineer's instincts and skill at practical problem-solving under pressure, often taking the lead in dealing with emergencies and being unafraid to lend a hand in manual work. A cable was finally completed in
August 5.
Disaster and triumph
Thomson's fears were realised and Whitehouse's apparatus proved insufficiently sensitive and had to be replaced by Thomson's mirror galvanometer. Whitehouse continued to maintain that it was his equipment that was providing the service and started to engage in desperate measures to remedy some of the problems. He succeeded only in fatally damaging the cable by applying 2,000
V. When the cable failed completely Whitehouse was dismissed, though Thomson objected and was reprimanded by the board for his interference. Thomson subsequently regretted that he had acquiesced too readily to many of Whitehouse's proposals and had not challenged him with sufficient energy
[Ibid p.144].
A joint committee of inquiry was established by the
Board of Trade and the Atlantic Telegraph Company. Most of the blame for the cable's failure was found to rest with Whitehouse
["Board of Trade Committee to Inquire into … Submarine Telegraph Cables', Parl. papers (1860), 52.591, no. 2744]. The committee found that, though underwater cables were notorious in their lack of
reliability, most of the problems arose from known and avoidable causes. Thomson was appointed one of a five-member committee to recommend a specification for a new cable. The committee reported in October
1863["Report of the Scientific Committee Appointed to Consider the Best Form of Cable for Submersion Between Europe and America" (1863)].
In July
1865 Thomson sailed on the cable-laying expedition of the
SS Great Eastern but the voyage was again dogged with technical problems. The cable was lost after 1,200 miles had been laid and the expedition had to be abandoned. A further expedition in
1866 managed to lay a new cable in two weeks and then go on to recover and complete the 1865 cable. The enterprise was now feted as a triumph by the public and Thomson enjoyed a large share of the adulation. Thomson, along with the other principals of the project, was
knighted on
November 10 1866.
To exploit his inventions for signalling on long submarine cables, Thomson now entered into a partnership with
C.F. Varley and
Fleeming Jenkin. In conjunction with the latter, he also devised an
automatic curb sender, a kind of
telegraph key for sending messages on a cable.
Later expeditions
Thomson took part in the laying of the French Atlantic
submarine communications cable of
1869, and with Jenkin was engineer of the Western and Brazilian and Platino-Brazilian cables, assisted by vacation student
James Alfred Ewing. He was present at the laying of the
Pará to
Pernambuco section of the Brazilian coast cables in
1873.
Thomson's wife had died on
June 17,
1870 and he resolved to make changes in his life. Already addicted to seafaring, in September he purchased a 126-
ton schooner, the
Lalla Rookh and used it as a base for entertaining friends and scientific colleagues. His maritime interests continued in
1871 when he was appointed to the board of enquiry into the sinking of the
HMS Captain.
In June
1873, Thomson and Jenkin were onboard the
Hooper, bound for
Lisbon with 2,500 miles of cable when the cable developed a fault. An unscheduled 16-day stop-over in
Madeira followed and Thomson became good friends with Charles R. Blandy and his three daughters. On
May 2 1874 he set sail for Madeira on the
Lalla Rookh. As he approached the harbour, he signalled to the Blandy residence
Will you marry me? and Fanny signalled back
Yes. Thomson married Fanny, 13 years his junior, on
June 24,
1874.
Over the period
1855 to
1867, Thomson collaborated with
Peter Guthrie Tait on a
text book that unified the various branches of physical science under the common principle of energy. Published in 1867, the
Treatise on Natural Philosophy did much to define the modern discipline of
physics.
|
Thomson's tide-predicting machine |
Thomson was an enthusiastic yachtsman, his interest in all things relating to the sea perhaps arising, or at any rate fostered, from his experiences on the
Agamemnon and the
Great Eastern.
Thomson introduced a method of deep-sea
sounding, in which a steel
piano wire replaces the ordinary land line. The wire glides so easily to the bottom that "flying soundings" can be taken while the ship is going at full speed. A pressure gauge to register the depth of the sinker was added by Thomson.
About the same time he revived the
Sumner method of finding a ship's place at sea, and calculated a set of tables for its ready application. He also developed a
tide predicting machine.
During the
1880s, Thomson worked to perfect the adjustable
compass in order to correct errors arising from
magnetic deviation owing to the increasing use of
iron in
naval architecture. Thomson's design was a great improvement on the older instruments, being steadier and less hampered by friction, the deviation due to the ship's own magnetism being corrected by movable masses of iron at the
binnacle. Thomson's innovations involved much detailed work to develop princples already identified by
George Biddell Airy and others but contributed little in terms of novel physical thinking. Thomson's energetic lobbying and networking proved effective in gaining acceptance of his instrument by
The Admiralty.
Charles Babbage had been among the first to suggest that a
lighthouse might be made to signal a distinctive number by occultations of its light but Thomson pointed out the merits of the
Morse code for the purpose, and urged that the signals should consist of short and long flashes of the light to represent the dots and dashes.
Thomson did more than any other electrician up to his time to introduce accurate methods and apparatus for measuring electricity. As early as 1845 he pointed out that the experimental results of
William Snow Harris were in accordance with the laws of
Coulomb. In the
Memoirs of the Roman Academy of Sciences for
1857 he published a description of his new divided ring
electrometer, based on the old electroscope of
Johann Gottlieb Friedrich von Bohnenberger and he introduced a chain or series of effective instruments, including the quadrant electrometer, which cover the entire field of electrostatic measurement. He invented the
current balance, also known as the
Kelvin balance or
Ampere balance (
sic), for the
precise specification of the
Ampere, the
standard unit of
electric current.
In
1893, Thomson headed an international commission to decide on the design of the
Niagara Falls power station. Despite his previous belief in the superiority of
direct current electric power transmission, he was convinced by
Nikola Tesla's demonstration of three-phase
alternating current power transmission at the
Chicago World's Fair of that year and agreed to use Tesla's system. In
1896, Thomson said "Tesla has contributed more to electrical science than any man up to his time."
Thomson remained a devout believer in
Christianity throughout his life and saw chapel as part of his daily routine,
[McCartney & Whitaker (2002), reproduced on Institute of Physics website] though he might not identify with
fundamentalism if he were alive today.
[Sharlin (1979) p.7] He saw his Christian faith as supporting and informing his scientific work, as is evident from his address to the annual meeting of the
Christian Evidence Society,
May 23,
1889.
[Thomson, W. (1889) Address to the Christian Evidence Society]One of the clearest instances of this interaction is in his estimate of the
age of the Earth. Given his juvenile work on the figure of the Earth and his interest in heat conduction, it is no surprise that he chose to investigate the Earth's cooling and to make historical inferences. Thomson believed in an instant of
Creation but he was no
creationist in the modern sense.
[Sharlin (1979) p.169] He contended that the
laws of thermodynamics operated from the birth of the universe and envisaged a dynamic process that saw the organisation and evolution of the
solar system and other structures, followed by a gradual "heat death". He developed the view that the Earth had once been too hot to support
life and contrasted this view with that of
uniformitarianism, that conditions had remained constant since the indefinite past. He contended that "This earth, certainly a moderate number of millions of years ago, was a red-hot globe ... ."
[Burchfield (1990)]After the publication of Sir
Charles Darwin's
On the Origin of Species in
1859, Thomson saw evidence of the relatively short habitable age of the Earth as tending to contradict an
evolutionary explanation of
biological diversity. He noted that the
sun could not have possibly existed long enough to allow the slow incremental development by
evolution--unless some energy source beyond what he or any other
Victorian era person knew of was found. He was soon drawn into public disagreement with Darwin's supporters
John Tyndall and
T.H. Huxley.
Thomson ultimately settled on an estimate that the Earth was 100,000,000 years old. Shortly before his death however,
Becquerel's discovery of
radioactivity and
Marie Curie's studies with
uranium ores provided the insight into the 'energy source beyond' that would power the sun for the long time-span required by the
theory of evolution. Though Thomson continued to defend his estimates, privately he admitted that they were most probably wrong.
In
1884, Thomson delivered a series of lectures at
Johns Hopkins University in the
U.S. in which he attempted to formulate a physical model for the
aether, a medium that would support the
electromagnetic waves that were becoming increasingly important to the explanation of
radiative phenomena.
[Kargon & Achinstein (1987)]. Imaginative as were the "Baltimore lectures", they had little enduring value owing to the imminent demise of the mechanical world view.
In
1900, he gave a lecture titled
Nineteenth-Century Clouds over the Dynamical Theory of Heat and Light. The two "dark clouds" he was alluding to were the unsatisfactory explanations that the physics of the time could give for two phenomena: the
Michelson-Morley experiment and
black body radiation. Two major physical theories were developed during the twentieth century starting from these issues: for the former, the
Theory of relativity; for the second,
quantum mechanics.
Albert Einstein, in
1905, published the so-called "
Annus Mirabilis Papers", one of which explained the photoelectric effect and was of the foundation papers of quantum mechanics, another of which described
special relativity.
A variety of physical phenomena and concepts with which Thomson is associated are named
Kelvin:
*
Kelvin material*
Kelvin wave*
Kelvin-Helmholtz instability*
Kelvin-Helmholtz mechanism*
Kelvin-Helmholtz luminosity*The
SI unit of temperature,
kelvin*
Kelvin transform in potential theory
Always active in industrial
research and development, he was a
Vice-President of the
Kodak corporation.
*
Fellow of the Royal Society of Edinburgh, 1847.
**
Keith Medal, 1864.
**
Gunning Victoria Jubilee Prize, 1887.
**President, 1873–1878, 1886–1890, 1895–1907.
*
Fellow of the Royal Society, 1851.
**
Royal Medal, 1856.
**
Copley Medal, 1883.
**President, 1890–1895.
*
Knighted 1866.
*
Baron Kelvin, of
Largs in the
County of
Ayr, 1892. The title derives from the
River Kelvin, which passes through the grounds of the University of Glasgow. His title died with him, as he was survived by neither heirs nor close relations.
*
Knight Grand Cross of the Victorian Order, 1896.
*One of the first members of the
Order of Merit, 1902.
*
Privy Counsellor, 1902.
*He is buried in
Westminster Abbey,
London next to
Isaac Newton.
Kelvin's works
*
Biography, history of ideas and criticism
*
*
Kelvin water dropper*
Kelvin Society of Glasgow*
Lord Kelvin Online*
Lord Kelvin's PatentsHeroes of the Telegraph at
Project Gutenberg*
Humorous website devoted to the "worship" of Lord Kelvin*
William Thomson: king of Victorian physics at
Institute of Physics website
Measuring the Absolute: William Thomson and Temperature, Hasok Chang and Sang Wook Yi (
PDF file)
