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On the 17th of December 1907, aged eighty-three years, died the Right Honourable Sir William Thomson, Baron Kelvin of Largs.
Adequately to set forth the life and work of a man who so
early won and who for so long maintained a foremost place
in the ranks of science were a task that is frankly impossible.
The greatness of a man of such commanding abilities and such
profound influence cannot rightly be gauged by his contemporaries,
however intimately they may have known him.
But if we may not attempt the impossible, we may at least
essay the task of setting clown in simple fashion some account
of his life and achievements.
William Thomson was born on June 26, 1824, in Belfast, being
the second son and fourth child of James and Margaret Thomson.
James Thomson (or Thompson, as he spelled his name up to the
age of twenty-four), who was at that time Professor of Mathematics
in the Royal Academical Institution of Belfast, was the son
of a small farmer at Ballynahinch, in County Down, Ireland,
where his ancestors had settled about the year 1641, when
they migrated from the lowlands of Scotland.
In 1830, when William was six years old, his mother died.
His father would never send his boys to school, but taught
them himself. In 1832, when William was eight years old, Professor
Thomson was offered the Chair of Mathematics at Glasgow, and
he with his family of six children accordingly removed from
Belfast. After his removal to Glasgow he still kept the education
of his sons in his own hands, and so it happened that in 1834
William Thomson, when in his eleventh year, matriculated as
a student in the University without ever having been at school.
He early made his mark by his progress in Mathematics and
Physical Science, and in 1840 produced an essay "On the
Figure of the Earth," which won him the University Medal.
He also read Greek plays with Lushington, Latin with William
Ramsay, Logic and Moral Philosophy. To the end of his life
he was in the habit of bringing out quotations from the classic
authors.
His fifth year as a student at Glasgow, 1839-40, was notable
for the impulse toward Physics which he received from the
lectures of Professor J. P. Nichol and from those of David
Thomson (a relation of Faraday), who temporarily took the
classes in Natural Philosophy during the illness of Professor
Meikleham. In this year William Thomson had systematically
studied the "Mécanique Analytique" of Lagrange
and the "Mécanique Celeste" of Laplace, both
mathematical works of a high order, and had made the acquaintance
– a notable event in his career – of that remarkable
book, Fourier's "Théorie analytique de la Chaleur."
On May 1st he borrowed it from the College Library. In a
fortnight he had read it completely through. The effect of
reading Fourier dominated his whole career thenceforward.
He took the book with him for further study during a three
months' visit to Germany. During his last year (1840-41) at
Glasgow he communicated to the Cambridge Mathematical Journal,
under the signature "P. Q. R." an original paper,
"On Fourier's Expansions of Functions in Trigonometrical
Series," which was a defence of Fourier's deductions
against some strictures of Professor Kelland.
He left Glasgow University after six years of study, without
even taking his degree, and on April 6th, 1841, entered as
a student at St. Peter's College, Cambridge, where he speedily
made his mark. As an undergraduate of seventeen he was handling
methods of difficult integration readily and with mastery,
as his paper, entitled "The Uniform Motion of Heat in
Homogeneous Solid Bodies, and its Connection with the Mathematical
Theory of Electricity," clearly showed.
Of Thomson's Cambridge career so much has been written that
it need only be very briefly touched on here.
He went up for his Tripos in 1845, and came out Second Wrangler.
He rowed in the University races of 1844, and won the Colquhoun
silver sculls; he helped to found the Cambridge University
Musical Society, and himself played the French horn in the
orchestra.
On leaving Cambridge Thomson went to Paris and worked in
the laboratory of Regnault at the Collège de France.
He was here four months, and it was here he made the acquaintance
of Biot, Liouville, Pouillet, Sturm and Foucault, of whom
he spoke in terms of admiration. Returning to Cambridge he
was made College Lecturer in Mathematics, and elected to a
Fellowship worth about £200 a year. Thomson was now
twenty-one years old, but had already established for himself
a growing reputation for his mastery of mathematical physics.
He had published about a dozen original papers, and had gained
experience in three Universities.
In 1846 the Chair of Natural Philosophy
at Glasgow became vacant by the death of Professor Meikleham,
and Thomson, at the age of twenty-two, was chosen to fill
it. His father, Professor James Thomson – he died in
1849 – still held the Chair of Mathematics, Professor
Thomas Thomson held that of Chemistry, while Professor Allen
Thomson occupied the Chair of Anatomy. William Thomson was
the youngest of the five Professor Thomsons then holding office
in Glasgow. He chose for the subject of his inaugural dissertation:
"De Motu Caloris per Terra Corpus."
This Professorship he continued to hold till he resigned
it in 1899, after continuous service of fifty-three years.
In the lecture theatre his manifest enthusiasm won for him
the love and respect of all students, even those who were
hopelessly unable to follow his frequent flights into the
more abstruse realms of mathematical physics. Over the earnest
students of natural philosophy he exercised an influence little
short of inspiration, an influence which extended gradually
far beyond the bounds of his own University.
The next few years were times of strenuous work, fruitful
in results. By the end of 1850, when he was twenty-six years
of age, he had published no fewer than fifty original papers,
mostly highly mathematical in character, and several of them
in French. Amongst these researches there is a remarkable
group which originated from his attendance in 1847 at the
meeting of the British Association.
But a more important event of that meeting was the commencement
of his friendship with Joule, a Manchester brewer, and Honorary
Secretary of the Manchester Literary and Philosophical Society,
who had for several years been pursuing his researches on
the relations between heat, electricity, and mechanical work.
Joule's paper, which he presented on this occasion. on the
mechanical equivalent of Heat, would not have been discussed
at all but for the intelligent remarks and observations of
a certain young man, William Thomson, who had two years previously
passed the University of Cambridge with the highest honour.
Thomson, though, at first scarcely grasping the significance
of the subject, threw himself heart and soul into the new
and strange doctrines that heat and work were mutually convertible,
and for the next six or eight years, partly in co-operation
with Joule, partly independently, he set his unique powers
of mind to unravel those mutual relations.
Thomson's mind was essentially metrical. He must measure.
he must weigh, in order that he might go on to calculate.
"I often say," he once remarked, "that when
you can measure what you are speaking about, and express it
in numbers, you know something about it; but when you cannot
measure it, when you cannot express it in numbers, your knowledge
is of a meagre and unsatisfactory kind; it may be the beginning
of knowledge, but you have scarcely, in four thoughts, advanced
to the stage of science, whatever the matter may be ..."
Even before his first meeting with Joule, in June, 1847,
he communicated to the Cambridge Philosophical Society a paper
"On an Absolute Thermometric Scale founded on Carnot's
Theory of the Motive Power of Heat, and Calculated from Regnault's
Observations." In this paper he set himself to answer
the question: Is there any principle on which an absolute
thermometric scale can be founded? He arrived at the answer
that such a scale is obtained in terms of Carnot's theory,
each degree being determined by the performance of equal quantities
of work in letting one unit of heat be transformed in being
let down through that difference of temperature. This indicates
as the absolute zero of temperature the point which would
be marked as –273° on the air-thermometer scale.
In 1849 he elaborated this matter in a further paper on "Carnot's
Theory," and tabulated the values of "Carnot's function"
from 1°C to 231°C. Joule, writing to Thomson in December,
1848, suggested that probably the values of "Carnot's
function" would turn out to be the reciprocal of the
absolute temperatures as measured on a perfect gaz thermometer,
a conclusion independently enunciated by Clausius in February,
1850. Independently of Joule, Mayer and Helmholtz had been
considering the same problems from a more general standpoint.
Helmholtz's famous publication of 1847, "Die Erhaltung
der Kraft" – " On the Conservation of Force"
(meaning what we now term Energy) was chiefly concerned with
the proposition, based on the denial of the possibility),
of perpetual motion, that in aIl the transformations of energy
the sum total of the energies in the universe remains constant.
In the years 1851 to 1854, Thomson formulated with scientific
precision, in a long communication to the Royal Society of
Edinburgh, the two great laws of thermodynamics – (1)
the law of equivalence discovered by Joule, and (2) the law
of transformation which he generously attributed to Carnot
and Clausius. Thomson never was grudging of the fame of independent
discoverers. "Questions of personal priority," he
wrote, "however interesting they may be to the persons
concerned, sink into insignificance in the prospect of any
gain of deeper insight into the secrets of nature."
Thomson never made any use of the conception of entropy
introduced by Clausius. In 1855 he introduced the wider conception
of "available energy" which is the foundation of
the later developments of thermodynamics.
In 1852, at the age of twenty-eight, William Thomson married
Margaret Crum, and resigned his Cambridge Fellowship. The
happiness of his life was, however, shadowed by his wife's
precarious health, necessitating residence abroad at various
times. In the summer of 1855 they stayed at Kreutznach, from
which place Thomson wrote to Helmholtz inviting him to come
to England in September to attend the British Association
meeting at Glasgow. He assured Helmholtz that his presence
would be one of the most interesting events of the gathering,
so that he hoped to see him on this ground, but also looked
forward with the greatest pleasure to the opportunity of making
his acquaintance, as he had desired this ever since the "Conservation
of Force" had come into his hands. Accordingly, on July
29, Helmholtz left Königsberg for Kreutznach to make
the acquaintance of Thomson before his journey to England.
On August 6th he wrote to Frau Helmholtz that Thomson had
made a deep impression on him. "I expected to find the
man, who is one of the first mathematical physicists of Europe,
somewhat older than myself, and was not a little astonished
when a very juvenile and exceedingly fair youth, who looked
quite girlish, came forward. He had taken a room for me close
by, and made me fetch my things from the hotel and put up
there. He is at Kreutznach for his wife's health. She appeared
for a short time in the evening, and is a charming and intellectual
lady, but is in very bad health. He far exceeds aIl the great
men of science with whom I have made personal acquaintance,
in intelligence, and lucidity, and mobility of thought, so
that I felt quite wooden beside him sometimes."
Faraday and Riess had observed that in certain cases the
gases produced by the discharge of sparks through water consisted
of mixed oxygen and hydrogen, and Helmholtz had conjectured
that in such cases the spark was oscillatory. Thomson determined
to test mathematically what was the motion of electricity
at any instant after making contact in a circuit under given
conditions. He founded his solution on the equation of energy,
ingeniously building up the differential equation and then
finding the integral. The result was very remarkable. He discovered
that a critical relation occurred if the capacity in the circuit
was equal to four times the coefficient of self-induction
divided by the square of the resistance. If the capacity was
less than this the discharge was oscillatory, passing through
a series of alternate maxima and minima before dying out.
If the capacity was greater than this the discharge was non-oscillatory,
the charge dying out without reversing.
This beautiful bit of mathematical analysis, which passed
almost unnoticed at the time, laid the foundation of the theory
of electric oscillations subsequently studied by Oberbeck,
Schiller, Hertz, and Lodge, and forms the basis of wireless
telegraphy. Fedderssen in 1859 succeeded in photographing
these oscillatory sparks and sent photographs to Thomson,
who with great delight gave an account of them to the Glasgow
Philosophical Society.
At the Eilinburgh Meeting of the British Association in
1854 Thomson read a paper "On the Mechanical Antecedents
of Motion, Heat, and Light." Starting with some now familiar,
but then novel, generalities about energy, potential and kinetic,
and about the idea of stores of energy, the author touched
on the source of the sun's heat and the energy of the solar
system, and then reverted to his favourite argument from Fourier,
according to which, if traced backwards, there must have been
a beginning to which there was no antecedent.
The Proceedings of the Royal Society of Great Britain for
1854 contain the investigation of cables under the title,
"On the Theory of the Electric Telegraph." Faraday
had predicted that there would be retardation of signals in
cables owing to the coating of gutta-percha acting like the
glass of a Leyden jar. Forming the required differential equation,
and applying Fourier's integration of it, Thomson drew the
conclusion that the time required for the current, at the
distant end, to reach a stated fraction of its steady value
would be proportional both to the resistance and to the capacity;
and as both of these are proportional to the length of the
cable, the retardation would be proportional to the square
of the length. This is the famous law of squares about which
so much dispute arose. This was followed by a further research,
"On Peristaltic Induction of Electric Currents,"
communicated to the British Association in 1855, and afterward
in more complete mathematical form to the Royal Society.
The story of the Atlantic cable, of the failure of 1857,
of the brief success of 1858, has so often been told that
it need not be emphasised here. Thomson, after the failure
of the first attempt, was called upon to assist more actively.
Of the part he played in preparation for the cables of 1865
and 1866, suffice it to say that throughout the preparations,
the preliminary trials, the interrupted voyage of 1865, when
1,000 miles were lost, the successful voyage of 1866, when
the new cable was laid and the lost one recovered from the
ocean and completed, Thomson was the ruling spirit whose advice
was eagerly sought and followed.
On his return he was knighted. He had in the meantime made
further improvements in conjunction with Cromwell Varley.
In 1867 he patented the siphon recorder, and in conjunction
with Fleeming Jenkin, the curb-transmitter. He was consulted
on practically every submarine cable project from that time
forth. He established a partnership with Varley and Jenkin,
as consulting engineers, which proved a highly profitable
professional connection.
When, in 1861, Sir Charles Bright and Mr. Latimer Clark
proposed the names of ohm, volt, and farad for the practical
units based on the centimetre-gramme-second absolute system,
Sir William Thomson gave a cordial support; and on his initiative
was formed the famous Committee of Electrical Standards of
the British Association, which year by year has done so much
to carry to perfection the standard and the methods of electrical
measurement.
He was largely responsible for the international adoption
of the system of units by his advocacy of them at the famous
Paris congress of 1881, in which Helmholtz, Mascart and Werner
von Siemens took such prominent part, and of which Eric Gerard
was sectional secretary. He was an uncompromising advocate
of the metric system, and lost no opportunity of denouncing
the "absurd, ridiculous, time-wasting, brain-destroying
British system of weights and measures."
Faraday and Fourier had been the heroes of Thomson's youthful
enthusiasm; and, while the older mathematicians shook their
heads at Faraday's heretical notion of curved lines of force,
Thomson had, in 1849 and 1850, developed a new theory with
all the elegance of a mathematical disciple of Poisson and
Laplace, discussing solenoidal and lamellar distributions
by aid of the hydrodynamic equation of continuity. To Thomson
we owe the terms "permeability" and "susceptibility,"
so familiar in the consideration of the magnetic properties
of iron and steel. He also coined many other terms which have
come into use, including " thermo-dynamics" and
" kinetic energy."
In the winter of 1860-61 Thomson met with a severe accident,
which left him with a slight limp for the rest of his life.
It was about this period that he engaged with his friend Professor
P.G. Tait of Edinburgh in the production of a text book of
Natural Philosophy for the use of their students. Their idea
was to cover the whole range of physics, but as the work grew
under their hands, it never reached beyond the first of the
projected four volumes, and covered only Dynamics, including
Elasticity and allied topics.
The first part of Thomson and Tait's "Treatise on Natural
Philosophy" was published in 1867, the second part only
in 1874. But, fragmentary as the treatise was, it set the
teaching of dynamics on a new basis, and wrought a revolution
in the text-books of natural philosophy.
Thomson's contributions to the theory of elasticity are
no less important than those he made to other branches of
physics. He wrote the articles on Elasticity and Heat for
the Encyclopledia Britannica of 1878. In 1867 he communicated
to the Royal Society of Edinburgh his famous paper "On
Vortex Atoms." Helmholtz had published a mathematical
paper on the hydrodynamic equations of vortex motion, proving
that closed vortices could not be produced in a liquid perfectly
devoid of internal friction. Thomson seized on this idea.
If no such vortex could be artificially produced, then if
such existed it could not be destroyed. But being in motion
and having the inertia of rotation, it would have elastic
and other properties. He showed that vortex-rings (like smoke-rings
in air) in a perfect medium are stable, and that in many respects
they possess the qualities essential to the properties of
material atoms – permanence, elasticity, and power to
act on one another through the medium at a distance. The different
kinds of atoms known to the chemist as elements were to be
regarded as vortices of different degrees of complexity. Though
he seemed at the end of his life to doubt whether the vortex-atom
hypothesis was adequate to explain aIl the properties of matter,
and was not satisfied with the proof of the permanence of
vortex motions, the conception remains to aIl time a witness
to his extraordinary powers of mind.
In 1870 Lady Thomson, whose health had been failing for
several years, died. In the same year the University of Glasgow
was removed from the old College to its present site on Gilmore
Hill, overlooking the Kelvin burn.
For many years Thomson's sailing yacht, the Lalla Rookh,
was conspicuous, and he was an accomplished navigator. His
experiences in cable-laying had taught him much, and in return
he was now to teach science in navigation. First he reformed
the mariners' compass, lightening the moving parts to avoid
protracted oscillations, and shortening the needles to facilitate
the correction of the quadrantal and other errors arising
from the magnetism of the ship's hull. At first the Admiralty
would have none of it. Even the Astronomer Royal condemned
it. "So much for the Astronomer Royal's opinion,"
he ejaculated. But the compass won its way, first with the
Mercantile Marine, and then was universally adopted in the
Navy. The compass, as well as his galvanometers and siphon
recorders, and other instruments were constructed by the optical
firm of James White of Glasgow. In this business Thomson became
a partner, and later the principal owner and director. He
was an exceedingly able judge of good workmanship, and a keen
man of business.
Dissatisfied with the clumsy appliances used in sounding,
when the ship had to be stopped before the sounding line could
be let down, he devised the now well-known apparatus for taking
flying soundings by using a line of steel piano wire. He was
vastly interested in the question of the tides, not merely
as a sailor, but because of the interest attending their mathematical
treatment in connection with the problems of the rotation
of spheroids, the harmonic analysis of their complicated periods
by Fourier's methods, and their relation to hydrodynamic problems
generally. He invented a tide-predicting machine, which will
predict for any given port the rise and fall of the tides,
which it gives in the form of a continuous curve recorded
on paper; the entire curves for a whole year being inscribed
by the machine automatically in about four hours. Further
than this, adopting a beautiful mechanical integrator, the
device of his ingenious brother, Professor James Thomson,
he invented a harmonic analyser – the first of its kind
– capable not only of solving differential equations
of any order, but of analysing any given periodic curve, sure
as the tidal records, and exhibiting the values of the coefficients
of the various terms of the Fourier series.
Wave problems always had a fascination for him, and the
work of the mathematicians Poisson and Cauchy, on the propagation
of wave-motion were familiar studies. In 1871 Helmholtz went
with Sir William Thomson on the yacht Lalla Rookh to the races
at Inveraray, and on Borne longer excursions to the Hebrides.
Together they studied the theory of waves, "which he
loved," says Helmholtz, "to treat as a race between
us." Almost the last publications of lord Kelvin were
a series of papers on "Deep Sea Ship Waves," communicated
between 1904 and 1907 to the Royal Society of Edinburgh.
In 1874, on June 17th, Sir William Thomson
married Miss Frances Anna Blandy, of Madeira, whom he had
met on cable – laying expeditions. Lady Kelvin, who
survives him, became the centre of his home in Glasgow and
the inseparable companion of aIl his later travels.
Throughout the seventies and eighties Sir William Thomson's
scientific activities were continued with untiring zeal. In
1876 he visited America, bringing back with him a pair of
Graham Bell's earliest experimental telephones.
Amongst the matters that cannot be omitted in any notice
of his life was Lord Kelvin's controversy with the geologists.
He had from three independent lines of argument inferred that
the age of the earth could not be infinite, and that the time
demanded by the geologists and biologists for the development
of life must be finite. He himself estimated it at about a
hundred million of years at the most. In vain did the naturalists,
headed by Huxley, protest. He stuck to his propositions with
unrelaxing tenacity but unwavering courtesy. "Gentler
knight there never broke a lance," was Huxley's dictum
of his opponent. His position was never really shaken, though
the later researches of Perry, and the discovery by Strutt
of the degree to which the constituent rocks of the earth
contain radioactive matter, the disgregration of which generates
internal heat, may so far modify the estimate as to increase
somewhat the figure which he assigned.
In 1871 he was President of the British Association at its
meeting in Edinburgh. In his Presidential Address, which ranged
, luminously over the many branches of science within the
scope of the Association, he hazarded the suggestion that
the germa of life might have been brought to the earth by
some meteorite.
With the advent of electric lighting about the year 1880
Thomson's attention was naturally attracted to this branch
of the practical applications of science. He never had any
prejudice against the utilisation of science for practical
ends. "There cannot," he wrote, "be a greater
mistake than that of looking superciliously upon practical
applications of science. The life and soul of science is its
practical application; and just as the great advances in mathematics
have been made through the desire of discovering the solution
of problems which were of a highly practical kind in mathematical
science, so in physical science many of the greatest advances
that have been made from the beginning of the world to the
present time have been made in the earnest desire to turn
the knowledge of the properties of matter to some purpose
useful to mankind."
And so he scorned not to devise his well-known instruments
and appliances for commercial use.
Lord Kelvin's patented inventions were very numerous. Without
counting in those since 1900, taken mostly in the name of
Kelvin and James White, they number 56. Of these 11 relate
to telegraphy, 11 relate to compasses and navigation apparatus,
6 relate to dynamo machines or electric lamps, 25 to electric
measuring instruments, 1 to the electrolytic production of
alkali, and 2 to valves for fluids. He was an independent
inventor of the zigzag method of winding alternators, which
the public knew under the Dame of Ferranti's machine, which
was manufactured under royalties payable to him. He was interested
even in devising such details as fuses and the suspension
pulleys with differential gearing by which incandescent lamps
can be raised or lowered.
In his Presidential Address to the Mathematical and Physical
Section of the British Association at York in 1881 he spoke
of the electrical transmission and storage of energy, and
of the possibility of utilising the powers of Niagara. He
also read two papers, in one of which he showed mathematically
that in a shunt dynamo best economy of working was attained
when the resistance of the outer circuit was a geometric mean
between the resistances of the armature and of the shunt.
In the other he laid down the famous law of the economy of
copper lines for the transmission of power.
Helmholtz, visiting him again in 1884, found him absorbed
in regulators and measuring apparatus for electric lighting
and electric railways.
At the same time he was revolving over the speculations
which later in the same year he was to pour out in such marvellous
abundance in his famous twenty lectures in Baltimore, "On
Molecular Dynamics and the Wave Theory of Light." These
lectures, delivered to twenty-one hearers, mostly accomplished
teachers and professors, were reported verbatim at the time,
and reprinted by him with many revisions and additions in
1904. Of this extraordinary work, done at the age of sixty,
it is difficult to speak. Day after day he led the twenty-one
"coefficients" who sat at his feet, through the
mazes of the solid-elastic theory and the spring-shell molecule,
newly invented in order to give a conception how the molecules
of matter are related to the ether through which light-waves
are propagated. Part of the extreme interest of the course
arase from the circumstance that he had neither written out
the lectures beforehand, nor had even prepared a consistent
programme. Admitted to the very laboratory of his thoughts,
his hearers became eyewitnesses of his methods, his amazing
intuitive grasp, his headlong leaps, his mathematical agility,
his perpetual recurrence to physical interpretations, his
vivid use of mechanical analogies and his incessant resort
to models, actual or imaginary, by which his meaning could
be conveyed. His audience began to see that here was a man
who thought things out for himself from first principles,
making discoveries even while lecturing, and enjoying the
surprises that some of the things he was newly discovering
for himself had already been discovered by others. AIl his
life he had been endeavouring to discover a rational mechanical
explanation for the most recondite phenomena – the mysteries
of magnetism, the marvels of electricity, the difficulties
of crystaIlography, the contradictory properties of ether,
the anomalies of optics. While Thomson had been seeking to
explain electricity and magnetism and light dynamically, or
as mechanical properties, if not of matter, at least of ether,
Maxwell (the most eminent of his many disciples) had boldly
propounded the electromagnetic theory of light, and had drawn
aIl the younger men after him in acceptance of the generalisation
that the waves of light were essentially electromagnetic displacements
in the ether. Thomson had never accepted Maxwell's theory.
It is true that in 1888 he gave a nominal adhesion, and in
the preface which, in 1893, he wrote to Hertz's "Electric
Waves." he himself uses the phrase "the electromagnetic
theory of light, or the undulatory theory of magnetic disturbance."
But later he withdrew his adhesion, preferring to think of
things in his own way. Thomson's Baltimore lectures, abounding
as they do in brilliant and ingenious points, and ranging
from the most recondite problems of optics to speculations
on crystal rigidity, the tactics of molecules and the size
of atoms, leave one with the sense of their being a sort of
protest of a man persuaded against his own instincts, and
struggling to find new expression of his thoughts so as to
retain his old ways of regarding the ultimate dynamics of
physical nature. The lectures were revised and extended by
him, but were published as a volume only in 1904.
One characteristic of aIl Lord Kelvin's teaching was his
peculiar fondness for illustrating obscure notions by models.
Possibly he derived this habit from Faraday; but he pushed
its use far beyond anything prior. He was never satisfied
until he could make a mechanical model to illustrate his ideas.
This use of models is indeed to be found in the work of
every follower of Faraday. Maxwell designed physical models
as we have seen. FitzGerald conceived a remarkable model of
the ether. Andrew Gray has liberally employed them. The work
of Sir Oliver Lodge teems with models of an sorts. It has
become characteristic of the tone and temper of British physicists,
of none more than of lord Kelvin. Where Poisson or Laplace
saw a mathematical formula, Kelvin with true physical imagination
discerned a reality which could be roughly simulated in the
concrete. And throughout aIl his mathematics his grip of the
physical reality never left him. According to the standard
that Kelvin set before him, it is not sufficient to apply
pure analysis to obtain a solution that can be computed. Every
equation, "every line of the mathematical process must
have a physical meaning, every step in the process must be
associated with some intuition, the whole argument must be
capable of being conducted in concrete physical terms."
In other words, Lord Kelvin, being a highly accomplished mathematician,
used his mathematical equipment with supreme ability as a
tool: he remained its master and did not become its slave.
New Year's Day, 1892, brought the announcement that a peerage
of the United Kingdom had been conferred by Queen Victoria
upon Sir William Thomson. The title assumed was that of Baron
Kelvin of Largs. The name Kelvin was derived from the Kelvin
river, which flows past the buildings of the Glasgow University,
while the territorial addition "of Largs" referred
to his country mansion Netherhall, near the town of Largs,
in Ayrshire, which he built in 1875, and where he died.
In June, 1896, Glasgow University celebrated with a three
days' festival the Jubilee of Lord Kelvin's professorship.
It was attended by a large concourse of British and foreign
savants, who brought addresses and congratulations from every
university and academy of science in the civilised world.
He resigned his chair in October, 1899, being then in his
seventy-sixth year. But though he ceased to reside in Glasgow,
and retired to his country house at Largs, he continued to
take the most active interest in the progress of science and
in the operations of his instrument factory in Glasgow.
In his retirement much of his scientific thought centered
around a subject which had been in his mind in 1846 and had
often recurred: the possibility of formulating all the laws
of matter and ether in a single comprehensive theory based
on dynamics. This involved the conception of an ether which
could not only transmit light by transverse vibrations like
an elastic solid, but which must possess such a constitution
as to explain the propagation of magnetic and electrostatic
forces, and possibly also the existence of gravity. The vortex
theory of matter had become untenable, and the problems of
the molecular constitution of matter, with its related problems
of crystalline structure and of double refraction forced new
difficulties into view. The discoveries of Crookes followed
by those of Hertz and of Rœntgen started fresh trains
of thought, and still the comprehensive theory seemed as far
off as ever. At his jubilee he characterised as failure the
result of his most strenuous efforts during fifty-five years.
But he toiled on, seizing eagerly upon the notion of electrons
or electrions, as he called them – to explain the recondite
facts of molecular equilibrium and of the pyro-electric properties
of crystals, and in the added charters of his Baltimore lectures
he announced that he had found with the aid of electrions
– a dynamical explanation of every one of the difficulties
of twenty years before. His effort to find a dynamical theory
in terms of matter and energy, or (by means of the vortex
theory) in terms of matter and ether only, had ended in finding
it necessary to bring in electricity as a tertium quid. He
regarded the discovery of radium as bearing vitally on the
subject, and himself worked experimentally at the investigation
of the properties of radio-active bodies. His persistence
was unceasing and his activity of mind surprising.
Honours fell thickly on lord Kelvin in his later life. He
was President of the Royal Society from 1890 to 1894. He had
been made a Fellow of the Royal Society in 1851, and in 1883
had been awarded the Copper medal. His peerage was conferred
in 1892. He was one of the original members of the Order of
Merit founded by King Edward VII in 1902, was a Grand Officer
of the Legion of Honour, and held the Prussian Order Pour
le Mérite. In 1902 he was named a Privy Councillor.
In 1904 he was elected Chancellor of the University in which
he had filled the Chair of Natural Philosophy for fifty-three
years. He was a member of every foreign Academy, and held
honorary degrees from almost every University. In 1899 he
was elected an Honorary Member of the Institution of Electrical
Engineers, of which he had been twice President. He was elected
for a third time to the Presidency in the year of his death.
In 1906 he was elected First President of the International
Electrotechnical Commission, in the success of which he took
a deep interest, as clearly shown in his last letter to the
Central Office, dated November 8th, 1907, when he said: "I
am much pleased with what you tell me regarding the general
progress of the International Electrotechnical CommIssIon,
in its work, which is surely destined to bear good fruit throughout
the world."
His profound studies had led him again and again to contemplate
a beginning to the order of things, and he more than once
publicly professed a profound and entirely unaffected belief
in Creative Design.
Kindly-hearted, lovable, modest to a degree almost unbelievable,
he carried through life the most intense love of truth and
of insatiable desire for the advancement of natural knowledge.
Accurate and minute measurement was for him as honourable
a mode of advancing knowledge as the most brilliant or recondite
speculation. At both ends of the scale his pre-eminence in
the quest for truth was unchallenged. If he could himself
at the end of his long career describe his own efforts as
"failure," it was because of the immensely high
ideal which he set before him. "I know," he said
on the day of his jubilee, "no more of electric and magnetic
force, or of the relation between ether, electricity, and
ponderable matter, or of chemical affinity, than I knew and
tried to teach to my students in my first session." Yet
which of us has not learned much of these things because of
his work ?
After taking part in the British Association meeting of
1907 at Leicester, where he entered with surprising activity
into the discussions of radioactivity and kindred questions,
he went to Aix-les-Bains for change. He had barely reached
home at Largs in September when Lady Kelvin was struck down
with a paralytic seizure. Lord Kelvin's misery at her helpless
condition was intense. He had himself suffered for fifteen
years from recurrent attacks of facial neuralgia, and in 1906
underwent a severe operation. Under these afflictions he had
visibly aged, and the illness of Lady Kelvin found him little
able physically to sustain the anguish of the stroke. He wandered
distractedly about the corridors of his house unable at last
to concentrate his mind on work in hand. A chill seized him,
and after about a fortnight of prostration he sank slowly
and quietly away on December 17.
He was buried in Westminster Abbey, with national honours
on December 23, 1907, his grave being next to that of Newton. |
