3 From Rumford to Oersted

Our third five remarkable physicists were born in the twenty-five years from 1753

to 1777. Two came from France and one from each of America, England and

Denmark.

Sir Benjamin Thompson (Count Rumford) (1753–1814)

We return to America for our next profile. It is impossible to give a full

account of all the twists and turns of the picaresque life of Benjamin

Thompson in just a few pages. A convenient starting-point, for our purposes,

might be his arrival in London in the summer of 1776, when he was

already twenty-three; except that the early years of his life are significant for

what came later, so at least an outline is essential. Like Benjamin Franklin

he was born in New England, of humble parents, and spent part of his career

in America, part in Europe. However, Thompson and Franklin had very different

characters and whereas Franklin became a leading American patriot,

Thompson did not.

The future Sir Benjamin Thompson, Count Rumford, was born

Benjamin Thompson at Woburn, Massachusetts, on March 26, 1753; his

parents Benjamin and Ruth (n´ee Simonds) were farmers in a small way.

Owing to a boundary dispute, the same place was also known as Rumford

(now Concord), New Hampshire, whence the title he took later on in life. In

boyhood he early showed an inclination towards science. He was naturally

skilful in drawing, lettering and mechanical techniques, as well as ingenious

in the arrangement of the meagre apparatus at his disposal, and he devised

experiments in electrostatics, chemistry and mechanics. His interest in the

laws of nature extended to astronomy and, at the age of fourteen, he was

able to predict the time of occurrence of an eclipse. From a local doctor

with whom he boarded for a while he learned the rudiments of medicine

and surgery. Through the acquaintance of a mutual friend, Loammi Baldwin,

late of the colonial forces in the French and Indian War, young Thompson

attended lectures at Harvard College given by the celebrated professor

John Winthrop. Thompson and Baldwin learned from each other, in a selfimprovement

society of two. They tried to repeat Franklin’s experiment of

Benjamin Thompson (Count Rumford) (1753–1814) 75

flying a kite during a thunderstorm but merely ‘felt a general weakness in

their joints and limbs and a kind of lifeless feeling’. Baldwin went on to

become a prominent civil engineer, but his friend’s career developed quite

differently.

First Thompson made an advantageous marriage with a wealthy

widow, SarahWalker Rolfe, who was considerably older than himself. They

had a daughter, also called Sarah, of whom more later. His wife introduced

him into her social circle, including the Royal Governor of New Hampshire,

on whom he created such an impression that he was immediately offered

a commission as major in the 2nd New Hampshire Regiment. It is thought

that this must have been on the understanding that he would provide intelligence

for the British forces in theWar of Independence. However Thompson

spent the next year or so, he thought it prudent to leave the Boston area when

the city was taken by George Washington. Before long he was on his way

to England, having left his wife and daughter behind; he made no enquiries

after his wife for the next thirty years and none after his daughter for the

next twenty. He contrived to keep his whereabouts secret from them so that

the only way they could get in touch with him was through Baldwin.

When he arrived in London in the summer of 1776 the outcome of

the War of Independence was still in doubt and many American supporters

of the British side were in London expecting that a grateful nation would

provide for them until they could safely return home. They were generally

76 From Rumford to Oersted

disappointed in this, but not Thompson. He had a way of furthering his

fortunes by associating with those in power and before long he had become

a prot´eg´e of Lord George Germain. Germain had been out of favour with

the King and had allied himself with the Prince of Wales. When the Prince

succeeded to the throne he rewarded Germain by making him Secretary

of State for the Colonies, with responsibility for ensuring that the colonial

rebellions were suppressed. Naturally Thompson, as his number two, was

himself in a position to acquire power and influence. He secured the important,

and lucrative, task of equipping and victualling large numbers of British

troops.

Meanwhile he was developing a reputation in other ways. His interests

extended to military affairs, social reforms, animal husbandry and horticulture;

to each of these fields he applied the rigour of the experimental

scientist. From the very first months of his residence in England he used his

powers of observation to devise ways and means for the promotion of human

comfort and safety; in the economical use of fuel, the better designing of

chimneys and the more efficient use of firearms. This was technology rather

than science, but he was applying his scientific knowledge, as he was later

when he conducted experiments on ballistics. It was these activities that

led to his election to the Royal Society in 1780, at the age of twenty-seven.

After Germain had fallen from power, Thompson, never backward in

looking after himself, decided to move on. Sensing that the British cause

was lost in America, he returned to New York, where he was temporarily

given command of a Republican regiment. After returning to London

Thompson decided, on the strength of some limited military experience

acquired in America, to purchase a colonelcy; at this time commissions in

the British army were available for purchase, although influence was also

useful. He then set out for the continent in search of employment as a soldier

of fortune. Karl Theodor, the Elector of Bavaria, was an old-style ruler

who was looking for a scientist to ornament his court, and, when Colonel

Thompson presented letters of introduction and offered his services, the

Elector decided that he might be valuable both as a scientist and in a military

capacity. Permission from London for him to enter the service of the

Elector being forthcoming, together with a quite unexpected knighthood,

Sir Benjamin, as he was now entitled to call himself, set out to make himself

useful.

Among the services he provided for Karl Theodor was the clearance

of beggars from the streets of the capital. Bavaria was a poor country and

poverty was widespread. Rumford’s solution was to use the army to force

Benjamin Thompson (Count Rumford) (1753–1814) 77

the beggars into purpose-built workhouses, where they were confined and

set to work making military uniforms in return for their subsistence. This

was characteristic of Rumford’s attitude to social problems. Another service

was the construction of the ‘English Garden’, a popular feature of Munich to

this day. This was an attractive park laid out along the Neckar by the army

for the Elector but open to the public. The grateful Karl Theodor heaped

appointments on him; by 1790 he was privy councillor, major general of the

cavalry and adjutant general; two years later he was also lieutenant general

of the artillery, chief of staff and chief of the general staff. In 1791 the Elector

conferred on him the title of Count, amongst other honours, and from now

on we may refer to him as Count Rumford.

In Munich Thompson had two mistresses, who were sisters. The

older, Countess Baumgarten, was plump and buxom, a celebrated beauty

whose concurrent intimacy with Karl Theodor proved most useful to

Thompson. She bore him a daughter, Sophia, who was raised as a Baumgarten

child. The younger sister was Countess Nogarola. She was a slim,

athletic-looking woman with a strong intelligent face, who was not particularly

beautiful but whose keen mind and intellectual interests were quite a

match for Thompson’s own. They were intimate friends for many years. She

helped him with his correspondence in French and German and translated

some of his writings into Italian.

Meanwhile Rumford still found time for scientific work. The theory

of heat and its applications were his speciality; and he helped to undermine

the old caloric theory. His most important discovery was that a limitless

amount of heat can be produced by friction, which was conclusively

demonstrated in the cannon foundry of Munich, where the boring of gun

barrels produced large quantities of heat. He was a careful and methodical

experimenter, although the far-reaching implications of the results he had

obtained were not fully appreciated at the time.

In March 1793 London heard that ‘General Count Rumford’ had

obtained leave from the Elector to go to Italy for the sake of his health. Just

before leaving he heard from his American daughter Sarah that her mother

had died and Baldwin had revealed her father’s whereabouts to her. A young

American then arrived in Munich to ask for Sarah’s hand in marriage; he

was promptly sent away. Rumford then went off to Italy, first to Milan and

Pisa, then to Pavia, where he had some scientific contact with Volta, and

finally east to Verona, where his beloved Countess Nogarola lived with her

children. After some months in that area he went down to Florence, where

he had an affair with Lady Palmerston, who was then on the Grand Tour

78 From Rumford to Oersted

with her husband, and met her again in the south of Italy. After a year away

he began the return journey, stopping for several months with Countess

Nogarola en route.

After a year back in Munich Rumford found that life there was becoming

increasingly unpleasant. As his political power grew, so did persistent

rumours of mismanagement and self-aggrandizement; he reacted in a most

vindictive manner to those who opposed him. He persuaded the Elector to

grant him six months’ leave to go back to London to oversee the publication

of his new scientific work. He set out in October 1795, but, when

he arrived in London, a large trunk, containing ‘almost all the papers of

any consequence I possess in the world’, was removed from his carriage by

thieves. Although he lost all his scientific papers, probably what the thieves

were after was his private papers, which might have been useful to his

enemies. Rumford soon discovered that he was a political and social outcast

in London. He settled down to rebuilding his reputation in the capital and

publishing his scientific work. He wanted someone to look after him and

thought of his long-neglected daughter Sarah, with whom he had become

reconciled. He invited her to come over and join him. How he thought a

daughter he had abandoned years before in a New England village could

suddenly be transported to the fashionable salons of London and be an ornament

to society is hard to understand, but, if this is what he expected, Sarah

was a disappointment to him, as he was to Sarah. After a month he put her

into a fashionable girls’ school to learn the manners and etiquette of London

society.

Meanwhile Karl Theodor’s troubles had escalated. To go back some

years, when the Elector Maximilian II of Bavaria died in 1777, the junior

line of the Wittelsbachs, which had ruled that country for four and a half

centuries, became extinct. As Elector Palatine of the Rhine, Karl Theodor,

head of the family’s senior branch, was expected by virtue of arrangements

of long standing to inherit the Bavarian electorate and thereby reunite the

two Wittelsbach fiefs. This was acceptable to Austria only on conditions

that were unacceptable to Frederick the Great in Berlin, but in the end

Karl Theodor succeeded to the Munich throne and Bavaria lost some territory

to Austria. By 1792, however, Karl Theodor found himself threatened

not only by Austria, which remained dissatisfied, but also by the French

revolutionary armies. The latter overran the Palatinate and in 1795 invaded

Bavaria itself. The Elector, trapped between the forces of France and Austria,

appealed to Rumford to return from London and prepared to take refuge in

Saxony.

Benjamin Thompson (Count Rumford) (1753–1814) 79

Rumford arrived, accompanied by his daughter Sarah, just before Karl

Theodor fled to Dresden, and began by rallying the Bavarian troops. Thanks

to his knowledge of large-scale cooking and to his improvements in the

design of boilers and stoves, as well as his skill in conserving fuel, Rumford

was able to provide cheaply and comfortably for the large numbers of soldiers,

at first scattered and disorganized, who had converged on Munich to

be lodged and fed. When the Austrians tried to use Munich as a base from

which to resist the French, Rumford, with his customary firmness, tact and

presence of mind, managed to persuade both the invading armies to refrain

from molesting that city. This was no small achievement.

Rumford had served Bavaria in many capacities. On his return to

Munich, Karl Theodor offered him one more appointment, as head of the

General Police, but Rumford preferred to go back to Britain. The Elector

sought to honour him by designating him as his ambassador to the Court of

St James, and, under this supposed assignment, Rumford returned to London

in 1798. However, the count, as Sir Benjamin Thompson, was already a

British subject and could not therefore serve as a representative of a foreign

power, be it ever so friendly.

Rumford was by this time a wealthy man. After a long absence he

was able to mingle once again with his many friends and admirers in the

scientific world of the city, drawing their attention to the measures of

public and domestic economy which had made him famous in Germany.

He was welcomed on all sides for his ingenuity and philanthropy. Both the

Royal Academy and the Society for the Encouragement of Arts and Manufactures

(later the Royal Society of Arts) elected him to honorary membership.

In 1792 he had been awarded the Copley medal by the Royal Society for

‘various papers on the properties and method of communication of heat’.

Possibly through a desire to emulate Sir Godfrey Copley and hence perpetuate

his own name in the British scientific world, Rumford wrote to the Royal

Society in July 1796 offering ‘a fund of one thousand pounds, the interest on

which would be spent every second year as a premium to the author of the

most important discovery or improvement in the subjects of heat and light,

especially those applications which would contribute most to the good of

mankind’. The offer was accepted and the dies for a Rumford medal ordered

and made. Rumford himself received the first such medal in 1802.

Although the impossibility of serving as the Bavarian ambassador in

London was at first a severe blow to Rumford, he did not let himself remain

idle for long. His active mind turned towards a project that would afford

at once activity and, he hoped, advancement. His interests now centred

80 From Rumford to Oersted

themselves on a philanthropic organization that was at that time attracting

public notice, the Society for Bettering the Condition and Increasing the

Comforts of the Poor. One of its leading members wasWilliamWilberforce,

anti-slavery leader and prominent evangelical layman in the Church of

England. What this praiseworthy society was trying to do for the lower

orders of population by lessening their misery in one way should, in the

opinion of Rumford, be augmented by efforts towards increasing the efficiency

of their labours, for example by improving their mechanical skills.

Acting with the support of the society, Rumford drew up plans ‘for

forming by subscription, in the metropolis of the British Empire, a public

institution for diffusing the knowledge and facilitating the general introduction

of useful mechanical inventions and improvements, and for teaching by

courses of philosophical lectures and experiments the application of science

to the common purposes of life’. A committee chaired by Sir Joseph Banks

was formed, and the outcome was the Royal Institution of Great Britain,

which was incorporated on January 13, 1800 and granted a Royal Charter

by George III. Since the Royal Society had no laboratory facilities itself, it

became customary for its fellows to turn to the Royal Institution if there

were experiments they wished to see performed. Later it was often described

as ‘the workshop of the Royal Society’.

With characteristic enthusiasm and passion for details, Rumford

threw himself into the organization of the new institution. A building in

Albemarle Street was purchased and remodelled according to his plans –

complete with lecture room, repository for models, workshops and kitchens.

In order that possible patrons might not feel left out, Rumford engaged professors

and lecturers to provide scientific instruction for those of the upper

classes who might care to keep abreast of the times. Committees were set

up to suggest and supervise research in science and the useful arts. The programme

included a school for mechanics and a print shop for the publication

of research articles. It seemed as though every one of the count’s gamut of

interests, save the military, was wrapped up in this new socio-scientificphilanthropic

institution

For the educational programme the services of Thomas Young were

secured; his profile is given later. Unfortunately he was too erudite to make a

good lecturer for popular audiences, but his colleague Humphrey Davy made

up for this. Davy, who was already renowned for his discovery of the benefits

of nitrous oxide as an anaesthetic, was appointed assistant lecturer in

chemistry, director of the laboratory and assistant editor of the publications

of the Institution. He was allowed to occupy a room in the house, which was

Benjamin Thompson (Count Rumford) (1753–1814) 81

furnished with coals and candles, and paid one hundred guineas per annum.

His lectures drew large crowds, for he had a natural gift for making science

interesting to the layman and could hold his audiences by the infection of

his own enthusiasm. What he started soon became the chief characteristic

of the Royal Institution – a well-balanced combination of scientific research

and the exposition of its results in the lecture theatre.

Unfortunately the entire scheme was altogether too ambitious. The

institution could not be financially self-supporting, at least not in its early

days. Rumford, with his care for details and rigorous attitude towards the

fulfilment of his plans, could not cope with the situation he had created.

Once he was out of the country, some of his pet schemes were abandoned

on the grounds of economy. The school for mechanics, the culinary demonstrations

and the workshops for model-makers were soon discarded. On

reflection, education of the masses seemed less important than the popularization

of science among the upper classes. Of course all strata of the

population were welcome to visit the rooms and workshops, but the times

were not ripe for the establishment of trade schools.

When Rumford returned to Munich, he was pleased to see his natural

daughter Sophia Baumgarten had grown into a charming young lady.

However, the pleasures of his stay in Bavaria were eclipsed by his flattering

reception in Paris, his next port of call. He was presented to Napoleon

as a Bavarian general; the First Consul took an immediate liking to him,

showering him with special attention. He stayed altogether two months

in the French capital, sending reports to London and Munich on politics,

to Lady Palmerston on the social life and to Sir Joseph Banks on science

and scientists. As for Napoleon: ‘Bonaparte is a person endowed with very

uncommon abilities. And the more I see of him, and the more I consider

the wonderful things he has done, and is doing, the more I am disposed to

admire his genius, and to give credit to the wisdom of his plans, and the

purity of his intentions.’ Napoleon made great use of natural philosophers,

and Rumford as a famous visiting scientist found that he had an immediate

entr´ee to the highest political circles. He met Lafayette and Talleyrand,

dined with Berthollet, was introduced to Laplace, attended a session of the

Paris Academy and was elected to membership in two different classes,

namely the one dealing with mathematics and physics and the one dealing

with political economy. Most of all he was f ˆeted by the Parisian ladies.

When he returned to London Rumford found that the king ignored

him, while Lady Palmerston, offended by his glowing accounts of the ladies

of Paris, would not receive him. He tried to sort out the problems at the

82 From Rumford to Oersted

Royal Institution, which was already in financial difficulties. Unfortunately

differences kept arising between Rumford and the management of the institution,

which became so acute that he left London in May 1802, vowing

never to return. He again went first to Munich and then on to France. By

this time Napoleon’s campaigns were redrawing the map of Europe, and

England was targeted. Napoleon no longer singled him out as a person of

importance, never once spoke to him privately.

It was quite natural that the brilliant salons which Madame Lavoisier,

the widow of the great chemist, held regularly at her home in Paris would

attract a scientist of Rumford’s stature. A veritable galaxy of scholarship

was represented at these gatherings, not only French scientists such as

Arago, Berthollet, Biot, Lagrange and Laplace, but also scientists of other

nationalities, such as Charles Blagden, who courted her unsuccessfully,

and the famous Baron von Humboldt. Rumford’s international reputation,

together with his courteous manner and interests so akin to those of her late

husband, could not fail to impress the vivacious and yet serious-minded lady.

She was no doubt impressed by her new guest’s account of his work for the

poor of Bavaria and his improvement of the living conditions of the indigent

of London.

Marie Anne Pierrette Paulze had married Lavoisier when she was

thirteen years old. For the twenty-three years they lived together she acted

as his research assistant, librarian, collaborator and scientific confidante.

She was a gracious hostess to their constant flow of visitors, both French

and foreign, and, being the better linguist, translated papers for him. She

knew enough chemistry to edit and publish his great M´emoires de chimie,

which had been left in a very fragmented format the time he was guillotined

for being farmer-general in the oppressive taxation system. She continued

to be famous for her social events: a formal dinner party every Monday, an

‘at home’ every Tuesday, a musical soir ´ee every Friday. She was now 43 and

had been a widow for nine years, Rumford was 50 and had been a widower

for eleven. Before long their marriage was celebrated.

Sarah, who had returned to America in 1798, had not been told by her

father of this impending development until he wrote to her early in 1804:

‘I shall withhold this information from you no longer. I really do think

of marrying, though I am not yet absolutely determined on matrimony.

I made the acquaintance of this very amiable widow in Paris, who, I believe,

would have no objection to having me for a husband, and whom in all

respects would be a proper match for me. She is a widow, without children,

never having had any; is about my own age, she enjoys good health, is very

Benjamin Thompson (Count Rumford) (1753–1814) 83

pleasant in society, has a handsome fortune at her own disposal, enjoys a

most respectable reputation, keeps a good house, which is frequented by the

first philosophers and men of eminence in the science and literature of the

age, or rather of Paris. And what is more than all the rest, she is goodness

itself . . . she has been very handsome in her day, and even now at 46 or 48

is not bad looking; of a middling size, but rather en bon point than thin. She

has a great deal of vivacity and writes incomparably well.’

Rumford made another brief visit to Munich, where little had

changed. Madame Lavoisier came out to join him and together they returned

to Paris via Switzerland. She went on ahead of him to ensure that he would

be allowed into France, because by this time England and France were at

war again. They were married on October 24, 1805 and settled into a house

in the rue d’Anjou close to the Tuileries Gardens and the Champs Elys´ ees.

It cost 3000 guineas and was set in a beautiful two-acre garden. She decided

that she wished to be known as Countess Lavoisier de Rumford. Rumford

seemed to be very happy and he wrote to Sarah saying that ‘he had the best

of pinned hopes of passing my days in peace and quiet in this paradise of

a place’. However, before long she learnt that all was not well with the

new marriage. Although they had known each other for almost five years,

they soon discovered that they were incompatible and started arguing about

almost everything. The countess liked entertainment and small-talk, but

he preferred quiet contemplation and experiment. She liked good food and

wine, but his stomach could not take it, so he generally sat at a separate

small table when they had guests. He loved music but she did not care for

it. Most of all she objected to the way he kept altering the house and its

contents to suit his own tastes without any reference to hers.

Two months after the marriage he was writing to Sarah that, ‘between

you and myself, as a family secret, I am not at all sure that certain persons

were not wholly mistaken in their marriage, as to each other’s characters’.

At the end of the first year: ‘very likely she is as much disaffected towards

me as I am towards her. Little it matters with me, but I call her the female

dragon.’ On the second anniversary: ‘I am still here, and so far from things

getting better they get worse every day. We are more violent and more

open in our quarrels’. Things went from bad to worse. In April 1808 he

wrote to Sarah, describing his wife as the most imperious, tyrannical and

unfeeling woman that had ever existed, whose perseverance in pursuing an

object was equal to her profound cunning and wickedness. He said that he

could not call her a lady, that it was impossible to continue and spoke of

separation.

84 From Rumford to Oersted

Rumford had tired of social events and talking with people when he

would rather have been working on his essays or in his garden. She was

annoyed by his ceaseless alterations to their house, and there was friction

between the German servants he brought from Bavaria and her own,

who were French. Although they tried to make a success of the marriage,

after nearly four years of endless quarrels, some violent, it was annulled by

mutual consent. Countess Lavoisier de Rumford returned to her round of

salons while the count retreated to a property at Auteuil near the Bois de

Boulogne. Here he resided for the remainder of his days, devoting his energies

to arranging, beautifying and improving the grounds. He paid a final

brief visit to Munich, where he learned that Countess Nogarola had died

and Sophia, his illegitimate child by her sister, was very ill. He summoned

Sarah to Paris to keep him company. She arrived late in 1807, bringing the

news that his old friend Baldwin had died. She was pleased to see her father

so contented with his fine garden, string of lively horses and songbirds in the

dining room. He had renewed his scientific interests and began to frequent

the Paris Academy again. He was still on speaking terms with his ex-wife,

whom Sarah found very charming: ‘it was a fine match, could they but have

agreed’.

Sarah was with her father at the last, acting as his hostess when he

invited some of his old associates in the sciences to dine with him and discuss

some of the problems at the Royal Institution. There was also another

mistress named Victoire Lef`evre, who bore him a son, named Charles

Franc¸ois Robert Lef`evre, and it was his son, Rumford’s grandson, who succeeded

to the title in due course. Rumford appeared to be in good health,

but on August 21, 1814 he died suddenly of ‘a nervous fever’. The funeral,

which took place at the cemetery at Auteuil three days later, was a lonely

affair with only a handful of people at the graveside. He left the residue

of his estate to Harvard University to establish a Rumford Professorship,

which still exists. Its purpose is ‘to teach by regular courses of academical

and public lectures, accompanied by proper experiments, the utility of the

physical and mathematical sciences for the improvement of the useful arts,

and for the extension of the industry, prosperity, happiness and well-being

of society’.

In his declining years Rumford had lost most of his old friends and

made hardly any new ones. The generally accepted view is that this was

because he was an insufferable genius who treated people with whom he

had to work with such disdain and contempt that he simply made more and

more enemies as he grew older. One commentator wrote that ‘he was utterly

Jean-Baptiste Fourier (1768–1830) 85

devoid of humour and humanism; hard, brittle and self-centred to the last’.

Another wrote that he was ‘unbelievably cold-blooded, inherently egotistic

and a snob’, and yet another that ‘he was the most unpleasant personality

in the whole of science since Isaac Newton’.

After her father’s death Sarah stayed on at Auteuil until May 1815 but

thereafter moved between London and Paris until she returned to Concord

to end her days and died in 1852 in the very room where she had been born

seventy-nine years before. When asked about her father she would say ‘he

was fond of having his own way, even, as I fancied, to despite me’. ‘He could

go one way or the other. And it was invariably the case, that when quiet and

happy himself he was like others or, in other words, agreeable; but when

perplexed with cares or business, or much occupied, there was no living

with him.’

Jean-Baptiste Fourier (1768–1830)

Jean-Baptiste-Joseph Fourier, to give him his full name, is the most illustrious

son of Auxerre, the principal city of western Burgundy, where he

was born on March 21, 1768. Both his father Joseph, a master tailor originally

from Lorraine, and his mother Edmie died before he was ten years

old. Fortunately certain local citizens took an interest in the orphaned

boy’s education and secured him a place in the progressive Ecole Royale

86 From Rumford to Oersted

Militaire, one of a number of such schools run by the Benedictine and other

monastic orders. Science and mathematics were taught there, among other

subjects, and, while the boy displayed all-round ability, he had a special gift

for mathematics. He went on from there to complete his studies in Paris at

the Coll`ege Montagu. His aim was to join either the artillery or the engineers,

the branches of the army supposedly open to all classes of society,

but when he applied he was turned down. Although he could have been

rejected on medical grounds, the reason given by the minister was that only

candidates of noble birth were acceptable.

After this setback Fourier embarked on a career in the church. He

became a novice at the famous Benedictine Abbey of St Benoˆıt-sur-Loir,

where he was called on to teach elementary mathematics to other novices.

After taking monastic vows he became known as Abb´e (Father or Reverend)

Fourier, but instead of pursuing a career in the church he returned to Auxerre

to teach at the Ecole Militaire. By this time he was twenty-one and had

already read a research paper at a meeting of the Paris Academy.

During the first tempestuous years of the Revolution, Fourier was

prominent in local affairs. His courageous defence of victims of the Terror

led to his arrest by order of the notorious Committee for Public Safety

in 1794. A personal appeal to Robespierre was unsuccessful, but he was

released after Robespierre himself had been guillotined. Fourier then went

as a student to the short-lived Ecole Normale Sup` erieure. The innovative

teaching methods which had been introduced there made a strong impression

on him and it gave him the opportunity to meet some of the foremost

scientists of the day, including Lagrange, Laplace and Monge. The next year,

when the Ecole Polytechnique opened its doors, under its original name of

the Ecole Centrale des Travaux Publiques, Fourier was appointed assistant

lecturer to back up the teaching of Lagrange and Monge. However, before

long he fell victim to the forces of reaction and was arrested again. He had

an anxious time in prison but his colleagues at the Ecole successfully sought

his release.

In 1798 Fourier was selected to join an expedition to an undisclosed

destination. This proved to be Napoleon’s Egyptian adventure. Once the

military objectives had been secured, Berthollet and Monge established an

Egyptian Institute in Cairo, of which Fourier was made permanent secretary,

and the cultural arm of the expedition set to work studying the antiquities,

some of which were appropriated. On top of this activity Fourier was also

entrusted with some negotiations of a diplomatic nature and he even found

time to think about mathematics. He proposed that a report on the work

Jean-Baptiste Fourier (1768–1830) 87

of the Egyptian Institute be published and, on his return to France, was

consulted regarding its organization and deputed to write a historical preface

describing the rediscovery of the wonders of the ancient civilization.

When the Description de l’Egypte was published, Fourier’s elegant preface,

somewhat edited by Napoleon, appeared at the front of it.

Meanwhile Fourier had resumed his work at the Ecole Polytechnique.

Before long Napoleon, who had been impressed by his capacity for administration,

decided to appoint him prefect of the D´epartement of Is ` ere, based

at Grenoble and extending to what was then the Italian border. The office of

prefect was a demanding one, but it was during this period that Fourier wrote

his classic monograph on diffusion of heat entitled Th´eorie analytique de

la chaleur (On the Propagation of Heat in Solid Bodies) and presented it to

the Paris Academy in 1807. It was refereed by Lagrange, Laplace, Lacroix

and Monge. Lagrange was adamant in his rejection of several of its features

(especially the central concept of trigonometric or, as we say, Fourier series),

so its publication in full was blocked; only an inadequate five-page summary,

written by Laplace’s prot´eg´e Poisson, appeared. Later Fourier received

a prize from the academy for the work, but it was not until 1822 that his

theory of diffusion of heat was published. To quote from the preface to the

Th´eorie analytique de la chaleur, this ‘great mathematical poem’ as Clerk

Maxwell described it:

First causes are not known to us, but they are subjected to simple and

constant laws that can be studied by observation and whose study is

the goal of Natural Philosophy . . . Heat penetrates, as does gravity, all

the substances of the universe; its rays occupy all regions of space. The

aim of our work is to expose the mathematical laws that this element

follows . . . But whatever the extent of the mechanical theories, they

do not apply at all to the effects of heat. They constitute a special

order of phenomena that cannot be explained by principles of

movement and of equilibrium . . . The differential equations for the

propagation of heat express the most general conditions and reduce

physical questions to problems in pure Analysis that is properly the

object of the theory.

As prefect, Fourier’s administrative achievements included securing

the agreement of thirty-seven different communities to the drainage of a

huge area of marshland to make valuable agricultural land and the planning

of a spectacular highway between Grenoble and Turin, of which only the

88 From Rumford to Oersted

French section was built. Napoleon conferred on him the title of baron, in

recognition of his excellent work as prefect.

Fourier was still at Grenoble in 1814 when Napoleon fell from power.

The city happened to be directly on the route of the party escorting the

Emperor from Paris to the south and thence to Elba; to avoid an embarrassing

encounter with his former chief, Fourier negotiated a detour in the route. No

such detour was possible when Napoleon returned on his march to Paris in

1815, so Fourier compromised, fulfilling his duties as prefect by ordering the

preparation of the defences – which he knew to be futile – and then leaving

the town by one gate as Napoleon entered by another. His handling of this

awkward situation did not adversely affect their relationship. In fact the

Emperor promptly gave him the title of count and appointed him prefect

of the neighbouring De´partement of the Rhoˆ ne, based at Lyon. However,

before the end of the Hundred Days Fourier had resigned his new title and

appointment in protest against the severities of the regime and returned to

Paris to concentrate on scientific work.

This was the low point in Fourier’s life. For a short while he was

without employment, subsisting on a small pension, and out of favour politically.

However, a former student at the Ecole Polytechnique and companion

in Egypt was now prefect of the D´epartement of the Seine. He appointed

Fourier director of the Statistical Bureau of the Seine, a post without arduous

duties but with a stipend sufficient for his needs.

Fourier’s last burst of creative activity came in 1817/8 when he

achieved an effective insight into the relation between integral-transform

solutions to differential equations and the operational calculus. There was

at that time a three-cornered race in progress among Fourier, Poisson and

Cauchy to develop such techniques. In a crushing response to a criticism by

Poisson, Fourier exhibited integral-transformsolutions of several equations

that had long defied analysis, and paved the way for Cauchy to develop a

systematic theory, en route to the calculus of residues.

In 1816 Fourier was elected to the reconstituted Acad´emie des Sciences,

but Louis XVIII could not forgive his acceptance of the Rhoˆ ne prefecture

from Napoleon and at first refused to approve the election. Diplomatic

negotiation eventually resolved the situation and his renomination the next

year was approved. He also had some trouble with the second edition of the

Description de l’Egypte (for now the references to Napoleon needed revision),

but in general his reputation was recovering rapidly. He was left in

a position of strength after the decline of the Soci´et´e d’Arcueil and gained

the support of Laplace against the enmity of Poisson. In 1822 he was elected

Jean-Baptiste Fourier (1768–1830) 89

permanent secretary of the Acad´emie des Sciences. In 1827, like d’Alembert

and Laplace before him, he was elected to the literary Acad´emie Franc¸ aise;

and he also succeeded Laplace as president of the council of the Ecole Polytechnique.

Outside France he was elected to the Royal Society of London.

Fourier’s health was never robust and, towards the end of his life, he

began to display peculiar symptoms that are thought to have been due to

a disease of the thyroid gland called myxoedema, which he had possibly

contracted in Egypt. As well as causing certain physical symptoms, this

disorder can lead to a dulling of the memory, which may account for the

mishandling of some of the memoirs he received as permanent secretary and

for the rambling character of those he wrote himself towards the end of his

life. Early in May 1830 he suffered a collapse and his condition deteriorated

until he died on May 16, at the age of sixty-two. The funeral service took

place at the church of St Jacques de Haut Pas, and he was buried in the

cemetery of P`ere Lachaise, close to the grave of Monge.

Throughout his career, Fourier won the loyalty of younger friends

by his unselfish support and encouragement; in his later years he helped

many mathematicians and scientists, including Abel, Dirichlet, Oersted and

Sturm. His scientific achievements lie mainly in the study of the diffusion

of heat and in the mathematical techniques he introduced to further that

study. His interest in the problem may have begun while he was in Egypt,

but the main work on it was done at Grenoble. Profound study of nature, he

used to say, is the most fertile source of mathematical discoveries, but the

mathematical discoveries he made have found a wide variety of applications,

as well as playing a highly important role in mathematical theory.

Fourier’s viewpoint was that of rational mechanics. He had a superb

mastery of analytical technique and this power, guided by physical intuition,

brought him success. Previously the equations used in the leading problems

of rational mechanics had usually been non-linear and they were solved by

ad hoc methods. Fourier created a coherent method by which the various

components of an equation and its solution in series were neatly identified

with the various aspects of the physical solution being analysed. He also

had a uniquely sure instinct for interpreting the asymptotic properties of

the solutions of his equations for their physical meaning. So powerful was

his approach that a full century passed before non-linear equations regained

prominence in rational mechanics.

In mathematical physics Fourier’s ideas have proved to be much more

fruitful than those of Laplace. He also had a long-standing interest in the

theory of equations and was trying to complete a book on the subject towards

90 From Rumford to Oersted

the end of his life. Some of his ideas on the subject evolved into Sturm’s

theorem, whereas others have recently found applications in the theory of

linear programming. He was also interested in dynamics and in the theory of

probability. As a mathematician, Fourier had as much concern for practical

problems of rigour as anyone in his day except Cauchy and Abel, but he could

not conceive of the theory of limiting processes as a meaningful exercise in

its own right. Poisson and Biot, outclassed as rivals in the theory of diffusion

of heat, tried for years to belittle Fourier’s achievements.

The later history of thermodynamics is complex. After Fourier, the

next important advances in understanding the nature of heat were due to

the theoretician Sadi Carnot, set out in his great memoir of 1824 Reflexions

sur la puissance motrice du feu (Reflections on the Motive Power of Fire).

Although Fourier, with other academicians, heard him lecture on his theories,

he did not seem to have appreciated their importance; after Carnot

died at the age of thirty-six they were neglected for years.

Thomas Young (1773–1829)

We now return to England. Quakers, members of the Religious Society of

Friends, were widely respected for their integrity as men of business; they

adopted a distinctive mode of dress, refused to take oaths and contributed

many distinguished men to science in eighteenth-century England. Thomas

Young, mentioned earlier, was one of them. His limited influence on science

was the result of his personality, his poor choice of methods of communication

and his frequent changes of occupation. He published sporadically,

often in obscure and inappropriate ways; his prose was awkward and his

Thomas Young (1773–1829) 91

mathematics inadequate. He was a gentleman scientist with many good,

even brilliant, ideas who lived to see others receive the credit and fame for

completing what he had begun. He made acute suggestions, but left them

for others to develop. The German scientist Helmholtz, whose work was

considerably influenced by Young’s ideas, gave his opinion that

he was one of the most clear-sighted men who have ever lived, but he

had the misfortune to be too greatly superior in sagacity to his

contemporaries. They gazed at him with astonishment, but could not

always follow the bold flights of his intellect, and thus a multitude of

his most important ideas lay buried and forgotten in the great tomes of

the Royal Society of London, till a later generation in tardy advance

made his discoveries and convinced itself of the accuracy and force of

his inferences.

Thomas Young was born in the village of Milverton, near Taunton,

Somerset, on June 13, 1773. His father, of the same name, was a cloth

merchant, banker and landowner. He and his wife Sarah (n´ee Davis) were

Quakers. Thomas was their eldest son, in a family that grew to nine.

Perhaps because of the size of the family, he was sent to live until the age of

seven with his maternal grandfather, Robert Davis of Minehead, who was

an enthusiastic classicist.

Thomas was a precocious child, with a phenomenal memory, especially

for languages. He could read by the age of two. The first school he

went to, a boarding school in Bristol, had nothing to teach him. After a year

back in Milverton, where he read science books borrowed from a neighbour,

he went to a school at Compton, Dorset, where he not only studied classics,

mathematics and natural philosophy but was also taught practical skills.

Young very early showed real mathematical ability. Prodigies tend to excel

in languages, mathematics or music.

After leaving school, at the age of 13, he returned to Milverton and

studied various Near-Eastern languages, including Syriac (western Aramaic)

and Hebrew. He also began making optical instruments and is said before

long to have mastered Newton’s Opticks and Principia. In 1787, aged only

fourteen, he went to join the grandson of the Quaker banker David Barclay.

The boy, named Hudson Gurney, was being educated privately, and it was

thought that he should have a companion in his studies, but to some extent

Thomas Young also acted as tutor to the younger boy. The two became

life-long friends; later Hudson Gurney became well known as an antiquary,

writer and politician.

92 From Rumford to Oersted

Although Barclay usually spent most of the year at his country house

near Ware in Hertfordshire, he generally resided for four of the winter

months in London. So during the five years Thomas Young spent in the

Barclay household, he was partly in London, where there were lectures he

could attend and libraries he could use. It was during one of the London

visits that he came to the notice of his great-uncle Richard Brocklesby,

who was prominent in the medical world. A fellow of the College of Physicians

and of the Royal Society, he had written on the therapeutic value of

music and had produced a standard treatise on military hygiene. Brocklesby

was immensely impressed by the accomplishments of his brilliant young

relative.

In 1789, in the middle of his time with the Barclays, Young was taken

ill with suspected consumption. Brocklesby succeeded in restoring him to

health and advised him to take more care of himself. At Brocklesby’s London

residence Young met most of the distinguished literary men of the day and

impressed them with his classical scholarship. On the advice of his greatuncle,

he took up medicine with a view to succeeding to his practice once he

qualified. In 1793 he entered St Bartholomew’s Hospital and in the following

year was elected to the Royal Society for an original paper on the action of the

ciliary muscles in the accommodation of the eye. The Duke of Richmond,

a man of the world, wrote to Brocklesby, who was his medical adviser:

But I must tell you how much pleased we all are with Mr Young.

I really never saw a young man more pleasing and engaging. He seems

to have already acquired much knowledge in most branches, and to be

studious of obtaining more: it comes out without affectation on all

subjects he talks upon. He is very cheerful and easy without assuming

anything; and even on the peculiarity of his dress and Quakerism he

talked so reasonably, that one cannot wish him to alter himself in any

one particular.

The duke, who was Master-General of the Ordnance at the time, offered to

appoint the young man as his private secretary, but, as Young wrote to his

mother,

I have very lately refused the pressing offer of a situation which would

have been the most favourable and flattering introduction to political

life that a young man in my circumstances could desire. I might have

lived at a duke’s table, with a salary of £200 a year as his secretary, and

with hopes of a more lucrative appointment in a short time. I should

Thomas Young (1773–1829) 93

have been in an agreeable family, have had enough time to study, a

library, a laboratory and philosophical apparatus at my service; and I

was not ashamed to allege my regard for our Society as a principal

reason for not accepting the proposal.

As Quakers are pacifists, it might have been the military connection which

inspired his refusal.

Although body-snatching had reached scandalous proportions,

Edinburgh at this time was the most highly regarded place in Europe for a

medical education. Young spent the next year in the Scottish capital, studying

modern languages as well as medicine. While he was there he ceased

to display the outward characteristics of Quakerism, mixed in society and

learnt to play the flute, to sing and to dance. Having decided to spend the

next academic year in Go¨ ttingen he ended his stay in Scotland with an

ambitious tour of the Highlands, still something of an adventure.

The University ofGo¨ ttingen, known as the Georgia Augusta, had been

founded in 1727 on the model of Oxford and Cambridge by King George II

of Great Britain, who was also Elector of Hanover. The new foundation

attracted students from all over Germany and from elsewhere in Europe as

well. Although its endowments were more generous and it enjoyed greater

autonomy, it was still in many respects a typical German university of that

period. According to the writer Heinrich Heine, ‘Go¨ ttingen is renowned for

its university and its sausages; the inhabitants are divided into four classes:

students, professors, Philistines and cattle.’

In G¨ ottingen Young took full advantage of the excellent library and

other facilities. He was struck by the way that professors might entertain

students in their homes and yet completely ignore them if they passed them

in the street. He commented that ‘science here has one advantage that the

doctrines of both countries are well known here, while the English attend

very little to any opinion but those of their own country’. In addition to

medical studies he learnt horsemanship and devoted considerable attention

to music and other arts. At the end of the year he left with the degree of

doctor of physic, surgery and midwifery from the Georgia Augusta, having

submitted a thesis De corporis humani viribus conservatricibus. He travelled,

mainly on foot, to Dresden, where he spent a month studying the art

collections, and then returned to London, via Berlin and Hamburg, a remarkably

accomplished and educated young man. ‘His language was correct and

his utterance rapid.’ He was ‘emphatically a man of truth’ and ‘could not

bear the slightest degree of exaggeration’; he was ‘accustomed to reciprocate

94 From Rumford to Oersted

visits with the best society’ and was ‘always ready to take part in a dance

or a glee, or to join in any scheme of amusement calculated to give life or

interest to a party’.

In 1797, on Brocklesby’s recommendation, Young entered Emmanuel

College, Cambridge, where he spent two years as a fellow-commoner, which

gave him the right to dine with the fellows rather than with the other undergraduates.

He had been caught by a change in the regulations of the College

of Physicians; previously two years of university study had been required of

a medical practitioner, now it had to be two years at the same university.

The alternative was to return to Edinburgh for a second year, which would

have been far better professionally and avoid the problem of the religious

test which involved taking an oath. As a Quaker, in the first case of its kind,

he was given leave not to take the oath. Being technically a student, Young

found that the more distinguished senior members of the university were

just as aloof as they had been atGo¨ ttingen, but he made some friends among

the junior members, among whom he was known as ‘Phenomenon Young’.

He was seldom seen in the libraries, being mainly occupied with experimental

work on sound and light, including the phenomenon of interference, the

results of which he communicated to the Royal Society. He described what

he was doing in a letter to one of his scientific friends:

I amashamed to find how much the foreign mathematicians for these

forty years have surpassed the English in the higher branches of these

sciences. Euler, Bernoulli and d’Alembert have given solutions to

problems which have scarcely occurred to us in this country. I have

had particular occasion to observe this in considering the figure of

vibrating chords, the sound of musical pipes and some similar matters

in which I fancied I had hit on some ideas entirely new, but I was glad

to find them in part anticipated by Daniel Bernoulli in 1753 and 1762.

There are still several particulars respecting the gyration of chords and

formation of synchronous harmonics, the combination of sounds in

the air, the phaenomenon of beats, on which I flatter myself that I

shall be able to throw some new light.

Already he was beginning to follow Hooke and Huygens in regarding light

as a wave motion, like sound.

Not long after he had gone up to Cambridge his great-uncle died,

leavingYoung a fortune of £10 000, a large London house, a library and works

of art. In preparation for taking over his benefactor’s medical practice, Young

gained some further experience in the London hospitals and then established

Thomas Young (1773–1829) 95

himself in practice inWelbeck Street. While he continued his contributions

to literary scholarship and science, he often published anonymously to avoid

any suspicion that he might be neglecting his patients.

In 1800 Young, as we know, was appointed professor of natural philosophy

at the Royal Institution; he was also editor of its publications and

superintendent of its premises. As a lecturer to a popular audience he was

not a success; he displayed extraordinary erudition but his style was too

didactic and condensed. Friends advised him that his professorial responsibilities

were interfering too much with his medical work and so he resigned

his chair after only two years, to devote himself largely to medicine. In 1802

he was appointed secretary of the Royal Society, became foreign secretary

two years later and held that office for the rest of his life. In 1804, at the age

of thirty, he married an ‘extremely young’ lady named Eliza Maxwell, who

had Scottish aristocratic connections.

Young was awarded the degree of M.B. at Cambridge in 1803 and that

of M.D. five years later. He was elected fellow of the College of Physicians

in 1809, became censor in 1813 and 1823 and was Croonian Lecturer in

1822 and 1823. During the winters of 1809 and 1810 he gave courses of

lectures at the Middlesex Hospital, but these again were not a success with

the students. In 1811 he was appointed physician at the highly respected

St George’s Hospital, a position he held until his death. Yet as a medical

practitioner success eluded him and in 1814 he retired from practice. This

was not only an exciting time for medical research but also a period when

medical practice was being modernized. Perhaps Young was ahead of his

time.

Major changes of occupation were a feature of Young’s later life. He

published several papers dealing with life insurance and was appointed

inspector of calculations and physician to the Palladium Insurance Company.

He became secretary of the Commission on Weights and Measures

and of the Board of Longitude. In 1818 he was appointed superintendent of

the Nautical Almanac; his view that the almanac should, as in the past, supply

only information of importance in navigation brought him into conflict

with many astronomers of the day, who wished it to cater for their needs as

well. To a large extent these various activities were related to his position

as foreign secretary of the Royal Society, but he also returned to his early

interest in philology.

All knowledge of the meaning of the hieroglyphic inscriptions found

on Egyptian remains had been lost for 1300 years. Many unsuccessful

attempts to interpret them had been made during the eighteenth century,

96 From Rumford to Oersted

but it was thought that at least some of the characters represented sounds

and that those enclosed in an oval line represented proper names. When,

in 1790, a tablet, somewhat damaged, was discovered at Rosetta, at the

mouth of the Nile, with a decree of the priests inscribed on it in hieroglyphic

(sacred), enchorial (cursive) and Greek characters, it was realized that the

Greek text might provide a clue to the interpretation of the Egyptian inscriptions.

The tablet was placed on display in the British Museum. Impressions

of the inscription were circulated to scholars all over Europe, but

twenty years went by without much progress in solving the problem of interpretation.

Meanwhile more hieroglyphic inscriptions had been discovered

following Napoleon’s expedition to Egypt.

In 1813 Young started attempting to decipher the inscriptions on the

Rosetta stone and by the following year he had translated the ‘enchorial’, or

domestic, running script and had concluded that the enchorial was derived

from the hieroglyphic. Pressure of other work prevented him from doing

much more for some time, but he returned to the problem in the closing

years of his life and made remarkable progress. The illustrious Champollion

was a specialist in a field where Young was a gifted amateur, but at

least he set Champollion on the right track. Young was still working on an

Enchorial Egyptian Dictionary up to the end of his life; it was published

in 1830, shortly after his death. This was the most notable of a number of

works of scholarship dating from his last decade. Another that should be

mentioned is his work as a major contributor to the fourth edition of the

Encyclopaedia Britannica, published in 1819. His lengthy article ‘Egypt’

became famous; he also contributed a large number of the biographical

notices.

In the latter part of his life Young usually spent the period from

November to June each year in London and the rest of the year in the fashionable

south-coast resort of Worthing, where he tried unsuccessfully to

build up a medical practice. After 1815, when peace had been restored on

the continent, he made several visits to Paris. The first was in 1817, when

he met Arago, Laplace and Baron von Humboldt amongst others. Four years

later he returned to the continent for a more extended tour, including Italy.

In 1827 he received international recognition when, in succession to Volta,

he was elected to the select band of eight foreign associates of the Paris

Academy. The following year when he was in Paris again it was noticed

that his strength was declining. In London he moved from Welbeck Street

to a house in Park Square, not far away, and it was there that he died of heart

disease on May 10, 1829, at the age of fifty-six. He was buried in the vault of

Andr´e-Marie Amp`ere (1775–1836) 97

the family of his wife Eliza at Farnborough. A profile medallion was placed

in Westminster Abbey with an inscription referring to his achievements.

In his essay On the Cohesion of Fluids Young gave in nonmathematical

language the theory of capillary action soon after brought

forwards by Laplace independently. He was also the first to use the term

‘energy’ for the product of the mass of a body and the square of its velocity.

In the theory of elasticity he introduced the formula relating stress to strain

which we know as Young’s modulus, but characteristically his definition

is hopelessly obscure. His theory of tides explained more tidal phenomena

than had any previous one. Apart from his contributions to the theory of

light and sound, he wrote many important papers on medical subjects.

Young has been called the founder of physiological optics, building

on foundations laid by Kepler, Descartes, Huygens and others. He was the

first to prove conclusively that the accommodation of the eye for vision at

different distances was due to a change in curvature of the crystalline lens.

His memoir on the mechanism of the eye contained the first description and

measurement of astigmatism, a condition from which he suffered himself.

He also gave an explanation of colour blindness. When Young began to write

on physical optics the wave theory of light had made little headway against

its rival the corpuscular theory, which was favoured by Newton. Young

developed the wave theory, the vibrations being transverse to the ray, and

obtained many experimental results supporting that view, but his work

was little understood in his lifetime. Not long afterwards Fourier’s disciple

Augustin Fresnel contributed his mathematically sophisticated wave theory

of light, which went far beyond Young’s ideas.

Andr´e-Marie Amp`ere (1775–1836)

It is perhaps unfortunate that, because of the dates of birth, the profile of

the French physicist Andr´e-Marie Amp`ere must precede that of the Danish

physicist Hans Oersted, because it was Amp`ere who gave the first mathematical

treatment of electromagnetism, the marvellous discovery of

Oersted. The son Andr´e-Marie of Jean-Jacques Amp`ere and Jeanne-

Antoinette (n´ee Desuti`eres-Sarcey) was born about January 20, 1775 in Lyon,

the second city of France, where both sides of the family were dealers in

silks. Just before marriage Jean-Jacques had acquired a country estate at

Poleymieux-les-Monts-d’Or, a small village in the picturesque hills a short

distance up the river Sa ˆ one: this was used initially as a summer retreat

from the city and later as the family’s permanent home after he retired from

business in 1782. Thus, for the first seven years of his life, their son and his

98 From Rumford to Oersted

elder sister Antoinette were able to enjoy both the busy life of the city and

the peace of the country. Three years after this he acquired a younger sister

Josephine, of whom more later.

The interests of Jean-Jacques included Latin and French literature,

as well as several branches of science, and, being a follower of the social

philosopher Rousseau, he encouraged his son to educate himself by reading

the books in his extensive library (although an education on the lines laid

down in Emile might be all very well, according to Arago the discipline

of a public school might have had a most salutary influence on Amp` ere’s

character). The boy, who displayed unusual powers of concentration and

a prodigious memory, read his way through Diderot’s great encyclopaedia.

Having been forbidden the rigours of geometry because of his tender years,

he defied parental authority and worked out the material in the early books

of Euclid by himself. When he found that the classics of science tended to

be in Latin, he taught himself the language in order to be able to study the

works of Euler and his contemporaries. He read the M´ecanique analytique

of Lagrange and worked through all the calculations it contains.

Later he described the three most influential events in his life as his

first communion, which established him in the faith of his fathers, the

Eulogy of Descartes, which instilled in him a belief in the nobility of a life

in science, and the fall of the Bastille, which decided his political sentiments

Andr´e-Marie Amp`ere (1775–1836) 99

for his entire life. The first two years of the Revolution, ending in the

attempted flight of the royal family, had some impact, even in Poleymieux,

but at first Lyon was spared the excesses which culminated in the Terror.

The city, a royalist stronghold, was in the hands of the relatively moderate

Girondins. Jean-Jacques Amp`ere took on the responsibilities of magistrate

and presiding legal functionary of the police tribunal, but this led him into

trouble when the Jacobin government in Paris, supported by sympathisers

in Lyon itself, took control of the city by force. Jean-Jacques was arrested

and imprisoned, tried for having approved a warrant of arrest for one of the

leading Jacobins, found guilty and promptly guillotined.

This devastating experience left Amp`ere averse to violence and militarism.

His mother, a deeply religious person, now took charge of his education.

Fortunately the family property had been transferred into her name, so

that at least some of it was shielded from confiscation. A lengthy period of

depression, during which he occupied himself mainly with botanical studies,

was broken by a love affair with the daughter Cath´erine-Antoinette Julie

Carron of a local family in somewhat similar circumstances to his own.

After he had courted her assiduously for three years, they were married

in August 1799; their first and only child Jean-Jacques was born the next

year.

Already Amp`ere had begun publishing his first memoirs in mathematics

and these brought him to the notice of the highly centralized French

scientific community. At the same time he made some close and enduring

friendships among the intelligentsia of Lyon. He also undertook some private

tutoring of mathematics students and some teaching at local schools.

In 1802 he left the city to become professor of physics and chemistry at the

Ecole Centrale du D´epartement de l’Ain at Bourg-en-Bresse, which was to

be the scene of much of his early scientific work. Before the Revolution it

had been staffed by Jesuits, but, after a transitional stage, it was secularized

and renamed the Lyc´ee Lalande. The plan was for him to gain some teaching

experience before returning to Lyon to work in a new Lyc´ee that was being

established by Napoleon. Meanwhile he was living in Bourg while his wife

Julie was forty miles away in Lyon. In 1803 she died of what may have been

a malignancy, leaving their three-year-old son in his care.

Following this second major tragedy in his life, Amp`ere was appointed

to a post at the new Lyc´ee in Lyon, but after less than a year he decided

to move to the capital to make more of a name for himself in the world of

science. He was appointed r ´ep´ etiteur for analysis at the Ecole Polytechnique.

This meant that he was essentially a tutor to the students who were lectured

100 From Rumford to Oersted

to by the professor of analysis, initially Augustin Cauchy. By 1809 he had

been promoted to professor of analytical mathematics and mechanics and

had become a member of the Legion of Honour. All too soon he became

involved in the quarrels of the scientific community in the French capital

and came to regret leaving Lyon.

The period between 1804, whenAmp`ere arrived in Paris, and his death

in 1836 was a time of complex political and social change. He witnessed

the consequences of Napoleon’s coronation as emperor, his military successes

and subsequent defeat, the initial restoration of Louis XVIII in 1814,

Napoleon’s return for the Hundred Days, the second restoration of 1815 and

the revolution of 1830. No supporter of Napoleon, Amp`ere favoured the idea

of a paternal and enlightened sovereign as head of state.

As well as his chair at the Ecole Polytechnique, Amp` ere, as was normal,

collected a number of other posts. Notably, in 1808 he was appointed

inspector-general of the newly formed university system, a post that he held

almost continuously for the rest of his life. In 1814 he was elected to the

Paris Academy and ten years later he was appointed professor of physics

at the Coll`ege de France. This was a most fruitful period for his scientific

work, especially after 1820 when, inspired by Oersted’s discovery of electromagnetism,

he made most of the discoveries for which his name is so

renowned and collected them together in his great 1827 M´emoire sur la

th´eorie math´ematique des phenom`enes ´electrodynamiques, uniquement

d´eduite de l’exp ´erience (Memoir on the Mathematical Theory of Electrodynamic

Phenomena, Uniquely Deduced from Experiments). In this work,

which has been described as the Principia of electrodynamics, he introduced

the important distinctions between electrostatics and electric currents

and between current and voltage, demonstrating that current-carrying

wires exert a force on each other, and gave an explanation of magnetism in

terms of electric currents.

Unfortunately there was to be further misery in Amp` ere’s private life,

to some extent self-imposed. Another Lyonnais living in the capital, Jean-

Baptiste Potot, had a 26-year-old daughter Jeanne-Franc¸ oise, who went by

the name of Jenny. The surviving descriptions of her family are uniformly

disparaging: ‘it was a household as bourgeois as possible, in the pejorative

sense in which artists understand that word: narrow ideas, prejudices,

pretensions, living only for money and vanity, not having the least idea

of the sciences, exactly the opposite of what it should have been for a big

child as simple and modest as Amp` ere’. He courted Jenny with the same

passion that had animated his relationship with Julie. As soon as they were

Andr´e-Marie Amp`ere (1775–1836) 101

married and had started living together she began to distance herself from

him. Her interest in the marriage seemed to be mainly financial: after the

birth of a daughter, Josephine-Albine, Amp`ere was granted a separation and

obtained custody of the child. To take care of his household, he persuaded

his mother and his sister Josephine to come to Paris, bringing his son Jean-

Jacques with them. Amp` ere’s friends in Lyon considered that he was being

selfish, and in fact his mother did not survive the move for more than eighteen

months. Meanwhile Amp`ere was having another love affair, but the

object of his attentions married someone else. In addition to all this, his

relations with his seven-year-old son by his first wife became strained.

Amp`ere found some solace in his mathematical work, writing to a

friend ‘I am going to take up mathematics again. I have some trouble at first,

but when I have overcome the initial repugnance, I no longer want to leave

the calculations. I still experience a great charm there when I can eliminate

every other thought and occupy myself with it alone, absolutely alone.’ He

completed a significant memoir on partial differential equations, presented

it to the Academy, made the customary social calls and, when the vote on

membership was taken in November 1814, was successful, beating Cauchy.

Ironically Cauchy was just at the beginning of his most creative period

whereas Amp`ere hardly touched mathematics afterwards, concentrating on

natural science instead. Unfortunately Amp`ere lacked perseverance; he was

always flying off to something new.

The middle-aged Amp`ere returned to the religious practices of his

youth. He sold off the family property at Poleymieux and bought a house in

Paris, where he took scholarly boarders who constituted a ready audience

when he needed someone to talk to, as he often did. He began taking more

interest in the education and ambitions of his son; the boy was quite bright,

learning to read at an early age, but in childhood was subject to violent

tantrums. By this time he was well-trained in languages, literature and the

sciences. Initially Amp`ere encouraged him to make a career in the chemical

industry, but Jean-Jacques was more interested in becoming a writer.

In the last ten years of his life Amp`ere gradually lost interest in science;

for example, he did not keep up with Faraday’s discoveries. Financial

problems became a daily concern. His sister ran up large debts maintaining

his household, while his son used the inheritance from his grandmother

to enjoy leisurely journeys abroad. Both father and son were temperamental,

given to bursts of anger interspersed with long periods of silence; it was

impossible for them to live under the same roof. In 1820 Jean-Jacques met the

celebrated Madame de R´ecamier and fell under her spell. This stimulated

102 From Rumford to Oersted

him to complete his first play, Rosamunde, which his father tried to get

produced. Madame de R´ecamier went off to Italy for a year, pursued by

Jean-Jacques. On his return to Paris he lost his interest in writing historical

dramas but gradually found a new one in literary history. He embarked on

an academic career, with such success that by 1833 he was teaching foreign

literature at the Coll`ege de France. He never married but maintained a

strained and unsatisfying relationship with Madame de R´ecamier until her

death in 1850.

Meanwhile Amp` ere’s daughter Albine became a source of concern.

She had married a military man with a prediliction for strong drink, violence

and gambling. He also had a dangerous habit of trying to avoid payment of

his gambling debts. After a tempestuous period in Paris he was sent off to

Louisiana, where two of his brothers had settled. Amp`ere himself displayed

remarkable patience and sympathy while all this was happening. After his

death Albine’s husband returned to Paris quite unreformed and before long

he was institutionalized. Albine herself became increasingly deranged. She

died in 1842; her father did not live to witness the final years of her unhappy

life.

Amp`ere was one of those who could obtain no inspiration when

seated; he preferred to stand up or walk around when thinking. Later in life

his behaviour became distinctly odd; his pupils made fun of him. His study

was open to all, but visitors found it difficult to leave it without playing a

game of chess with him. The serious financial problems he experienced in

later years were due partly to his expenditure on scientific instruments. His

scientific work came under criticism; among the academicians only Fourier

received his theories favourably. Outside France criticism was even more

severe. After 1829 Amp` ere’s years of scientific creativity had come to an

end and his health began to deteriorate. Suffering from bronchitis, laryngitis,

rheumatism and occasionally pneumonia, he wintered in the south

of France, with his son for company. He was in Marseille when he died

from pneumonia on June 10, 1836. Amp` ere’s remains were transferred to

the cemetery in Montmartre in 1869. The house at Poleymieux is now a

national museum, dedicated to his life and work.

Hans Christian Oersted (1777–1851)

At the opening of the nineteenth century very little was yet known

about electricity and magnetism. Hans Christian Oersted, who discovered,

almost by chance, the fundamental relation between them, was born in

the small Danish town of Rudjøbing on August 14, 1777. His father Søren

Hans Christian Oersted (1777–1851) 103

Christian Oersted was an impecunious pharmacist. His mother Karen (n ´ee

Hermansen) gave birth to another son, Anders Sandoe, the next year and

other children later. No formal schooling was available in Rudjøbing, which

is on the Baltic island of Langeland, but the resourceful pharmacist overcame

this problem. The two boys, while they were still young, were placed

with a German wigmaker, Christian Oldenberg, and his Danish wife. Their

father arranged for Oldenburg to teach them the German language and his

wife to help them learn to read and write. As for arithmetic, Oldenburg’s

knowledge was limited to addition and subtraction, but happily a local

youth imparted the arts of multiplication and division. From the mayor of

Rudjøbing they learnt a smattering of French, from the baker a little drawing

and from the local surveyor some geometry. Moreover, when Hans was

twelve years old he assisted his father in the pharmacy and thus acquired a

useful grounding in chemistry.

Various difficulties notwithstanding, Hans and Anders studied hard;

their intelligence was above average, and their parents used every available

means to encourage them. The two boys were so successful that they passed

with honours the entrance examination for the University of Copenhagen,

the only one in the country. There they received a little financial support

from the state and made up the remainder by teaching. They were both

interested in science, but the ambition of Anders was to become a lawyer,

104 From Rumford to Oersted

whereas Hans was more inclined towards literature and philosophy, subjects

in which he won prizes for his work. For his doctoral thesis he wrote about

the architectonics of natural metaphysics, for he was a passionate disciple

of Kant. It must be remembered that in much of Europe a doctorate is a first

degree.

The year 1800, memorable for Volta’s invention of the battery as a

source of electric current, saw Oersted again working in a pharmacy, this

time in Copenhagen, while the owner was away on a European tour. The

young man, aware of the discoveries which had just been made by Volta,

welcomed the opportunity this gave him for scientific research. On the

return of the owner of the pharmacy, who was professor of surgery at the

university, Oersted organized a scientific tour for himself, with the help of

a travel grant from the government. In Germany he found an abundance

of theory, but it was experimental work that interested him more. In Paris

he rashly gave a lecture, which was greeted by ridicule; it taught him to be

more careful in future. On the return leg of the tour he visited Brussels,

Leiden, Haarlem and Amsterdam. When he returned to Copenhagen he

found that the university building had been damaged by fire, and the physical

laboratory destroyed. While waiting for a suitable opening he gave some

public lectures, which showed that he had a gift for teaching. Within two

years Oersted was assistant professor of physics at the university and also

held a position at the military school. Three years later he produced a textbook

of mechanical physics and published in French an account of some

research he had undertaken on the identity of electric and chemical forces.

In 1812–13 Oersted made another tour of France and Germany. This

time he settled in Berlin for a while and published there in German the

research paper which already had appeared in French. The next year, when

he was back in Copenhagen, he married Inger Birgitte Ballum, whose father

was pastor of Kjelby, on the small island of Moer. At about the time of his

marriage, he associated himself with a movement to introduce the German

language into chemical terminology in place of French and Greek. In addition

he sought to raise science at the university to the status enjoyed by

theology.

Oersted usually devoted five hours a day to teaching and it was his

custom each month to present an account of new scientific advances in a

special lecture. It was at one of these that, in the year 1820, or thereabouts,

he made his historic discovery: that an electric current can displace a compass

needle. He assembled the apparatus, ready to try out after his lecture,

and asked the audience whether they would like to remain and see what

Hans Christian Oersted (1777–1851) 105

happened. At first the movement was so small, and its direction so unexpected,

that Oersted was unsure that it had been caused by the current. So

he tried again with a much stronger current and found that the deflection

was unmistakable. After the discovery had been announced he received honours

from all sides. The Royal Society of London, for example, awarded him

the Copley medal, while the Paris Academy elected him a corresponding

member.

Of all the congratulations he received from men of science, the most

emphatic were those of Thomas Young, who spoke of the marvellous discovery

that elevated Denmark to a rank in science it had not held since the

days of Tycho Brahe. In Germany it was said that Oersted’s experiments

in magnetism were the most interesting that had been carried out in that

domain of science for a thousand years. Faraday said of him that ‘his constancy

in the pursuit of his subject, both by reasoning and experiment, was

well rewarded in the winter of 1819 by the discovery of a fact that not a single

person beside himself [Oersted] had the slightest suspicion, but which, when

once known, instantly drew the attention of all who were able to appreciate

its importance and value’.

A third state-aided tour in 1822–3 took Oersted to England, where he

met Faraday, as well as to France and Germany. On his return he founded

the Danish Society for the Promotion of Scientific Knowledge, a major

vehicle for his efforts to raise the consciousness of progress in science among

the people of Denmark. In 1829 he became director of the Polytechnic

Institute in Copenhagen, a position he held for the rest of his life. He also

created a special laboratory for research on magnetism following a visit to

Go¨ ttingen, where he took advice from Carl Friedrich Gauss.

Towards the close of his life Oersted wrote to a friend that

in my family I am as happy as a man can be. I have a wife whom I love,

and children who are dear to me and who prosper. I have three sons –

of whom one is of age and is employed in the forestry service of the

king – and four daughters, of whom the eldest three are either married

or betrothed. My brother, who for some time was commissioner of the

king in our provincial parliament, has recently become a Minister of

State. As for me, I am still a professor and director of the polytechnic

school and secretary of the Royal Society of Sciences.

Oersted’s eldest daughter Karen married the professor of chemistry

at the university; another, Marie, married the pastor of a place in Zealand.

The youngest, Matilda, remained to cherish her father’s old friend Hans

106 From Rumford to Oersted

Christian Andersen, who bequeathed to her the manuscripts of his famous

stories. The husband of Oersted’s sister, Barbara Albertine, became president

of the Supreme Court of Norway. His brother Anders became prime minister

of Denmark. Another brother, Niels Randulph, an officer in the Russian

army, fell at the battle of Leipzig in 1813. They had come a long way from

the impecunious pharmacist of a generation or two before.

Oersted’s study of Danish literature was unceasing, and he published

a great deal of non-scientific work himself, usually related to his metaphysical

interests; he also wrote for the newspapers. In his later years he was

described as of open countenance, of florid complexion, somewhat stout, in

manners kindly, by nature gracious, loyal to the king, devoted to his country

and to the cause of humanity. In his scientific work he was often baffled but

never discouraged, his perseverance helped him to the end. The jubilee of

his association with the university in 1850 was celebrated by a torchlight

procession of his past and present students. The Danish government presented

him with a country house near Copenhagen, but he did not live to

enjoy it for long; within a few months he became ill and died peacefully in

the Danish capital on March 9, 1851.