6 From Ro¨ ntgen to Marie Curie

Our next five remarkable physicists were born in the twenty-three years from 1845

to 1867. Two came from England, two from Germany and one from Poland.

Wilhelm Conrad Ro¨ ntgen (1845–1923)

Wilhelm Conrad Ro¨ ntgen, the discoverer of X-rays, was born on March 27,

1845 in Lennep im Bergischen, a small town in the part of the Rhineland

which then belonged to Prussia. His father Friedrich Conrad Ro¨ ntgen was

a cloth manufacturer and textile merchant. The family of his mother

Charlotte Constanze (n´ee Frowein) were in the same line of business, and,

although they too came from Lennep, her parents lived in the Netherlands.

In 1848, when their son was three, the family moved to the town of

Apeldoorn in Holland, about a hundred miles distant, and as a result

they became Dutch citizens rather than Prussian. After elementary school,

Wilhelm attended a nearby private boarding school until at the age of seventeen

he entered the technical school in the provincial capital Utrecht.

There he lived with one of the teachers, and later recalled that

the father of this family was a fine scholar, a solid character and a

really splendid man who understood superbly the task of guiding

young persons along the correct path in life. The mother was a loving,

cultured and kindly woman who provided the proper atmosphere for a

full life, one of happiness and at the same time pleasant stimulation.

There was no time for foolish and stupid things, but much for creative

activities. Self-created amusements were offered at community

celebrations, but otherwise diligent work was demanded in serious

learning. That was a happy and equally rewarding time, and looking

back on the years of my youth, I have to add that I also went

horse-riding and ice-skating and generally busied myself in many

wholesome outdoor activities.

The young man was aiming to enter the famous old University

of Utrecht, but a problem arose, which was to cause him considerable

178 From Ro¨ ntgen to Marie Curie

difficulty. After an incident in which he refused to tell on another boy who

was at fault, R¨ ontgen was expelled from the technical school. He then went

to another school where he was prepared for university entrance but failed

to qualify. Even so, he attended lectures at the university for a short while,

but, because he was not a matriculated student, he would not have been able

to proceed to a degree. R¨ ontgen then decided to try instead for a place at the

Polytechnikum of Zu¨ rich (since 1911 part of the Eidgeno¨ ssische Technische

Hochschule, or ETH), which it was possible to enter by passing a special

examination. However, when he was all ready to sit this he went down

with an eye infection, but was admitted anyway.

‘Ro¨ ntgen was a tall, handsome youth who, with penetrating brown

eyes, looked soberly at the world’, wrote someone who knew him in Zu¨ rich:

He had a well spread nose and a large mouth. He had thick black wavy

hair, was clean shaven and always dressed well. His father supplied

him with sufficient money for clothes and extravagant fun and good

living. Usually his attire was a modest dark coat, grey trousers, a soft

wing collar with a large bow cravat, and a gold watch chain dangling

over his waistcoat. He was conservative and modest. Although he

disliked blatant conviviality, he was fun-loving, a popular young man

Wilhelm Conrad Ro¨ ntgen (1845–1923) 179

in a city where students were not always as serious as its sober

citizens. He often went riding along the lake-shore, but when

opportunity presented itself he would hire a fancy two-horse carriage

to ride in style through the city streets. He did not join one of the

Burschenschaften, which went in for carousing and duelling, but

enjoyed the company of other students from the Netherlands who had

their own informal club.

In Zu¨ rich at that time there was a scholarly innkeeper named Johann

Gottfried Ludwig who had been forced to leave his native Jena because of

suspected revolutionary activities. He settled in Zu¨ rich, where he purchased

an inn and married a Swiss girl, Elsabeth Gschwend. They had four children,

Lina Barbara, Anna Bertha, Hans Otto and Maria Johanna. R¨ ontgen was a

regular customer of the inn and became attracted by Bertha, the second

daughter of the innkeeper. She was a charming woman, tall and slender,

with a healthy and wholesome attitude towards life. When she became ill

and was hospitalized in a sanatorium he hired, on her thirtieth birthday, a

carriage drawn by four perfectly matched horses and driven by a top-hatted

coachman in splendid livery, and drove up to the sanatorium to present her

with a huge bouquet of red roses. It was agreed that they would marry once

his future was more secure.

Ro¨ ntgen’s studies were going well. He received his diploma as a

mechanical engineer in 1868 and then moved over to physics, in which field

he wrote his doctoral dissertation on thermodynamics, after taking a course

from the great Rudolf Clausius. When this was accepted his parents came to

Zu¨ rich to inspect his fiance´ e; they found her well-educated, of good family,

intelligent, of good character and very agreeable. However, they felt that,

although over thirty, she was not yet fully prepared for matrimony, so it was

agreed that she would go to Apeldoorn to learn cooking and other domestic

skills. At the same time Ro¨ ntgen obtained the position of assistant to the

physicist August Kundt, from whom he learnt the importance of taking the

utmost care in experimental work, often repeating an experiment over and

over again until the results were absolutely certain. When Kundt moved

to Wu¨ rzburg he took his assistant with him. However, Ro¨ ntgen found the

laboratory facilities there disappointing, a regular complaint throughout his

life.

At that time Friedrich Kohlrausch was one of the most eminent

German physicists. Ro¨ ntgen, in the course of some experiments on specific

heat, found some errors in the published work of Kohlrausch and sent

180 From Ro¨ ntgen to Marie Curie

a report to the prestigious Annalen der Physik und Chemie. When this first

scientific paper of his was accepted, he felt he could look forward to his

future with some confidence, and therefore get married. The wedding took

place in Apeldoorn at the beginning of 1872. A few months later Kundt

announced that he was moving again, this time to Strasbourg, and asked

Ro¨ ntgen to come with him. This he was glad to do, because his prospects

of advancement in Wu¨ rzburg seemed poor; even the first step of becoming

a Privatdozent was thwarted by his unsatisfactory school record.

After the Franco-Prussian war, Strasbourg (or Strassburg) lay in

German hands, and the ancient university was being reopened with new and

well-furnished buildings. For once he could not find fault with the equipment

in the laboratory. His elderly parents moved to Strasbourg to join

the young couple. In 1874 R¨ ontgen himself was appointed Privatdozent.

The following year he was offered a full professorship in physics at the

Agricultural Academy in Holdenheim, close to Stuttgart. After some hesitation

he accepted the post, but soon regretted doing so, because the experimental

facilities were so inadequate. When Kundt became aware of the

situation, he arranged for R¨ ontgen to return to Strasbourg as associate professor

of theoretical physics, at the age of thirty-four.

This second Strasbourg period was in many ways the most fruitful

of his professional life. His experimental work made good progress and he

published his results on a wide range of topics but particularly on the physical

properties of crystals. Soon he was ready for a full professorship and in

1879 the offer of one came from the University of Giessen, some 30 miles

north of Frankfurt, where he would be director of the institute of physics.

A new building for the institute had been agreed; not only could Ro¨ ntgen

choose the equipment for this, but he also had a say in the choice of his own

assistants. The Ro¨ ntgens found the small town of Giessen congenial and

were pleased when his parents did so too. In 1880 his mother died, and his

father died four years later. In 1887 the Ro¨ ntgens, realizing that they would

never have children of their own, decided to adopt the daughter of Bertha’s

brother Hans, their six-year-old niece Josephine Bertha.

Two years later Ro¨ ntgen made one of his most important discoveries

when he demonstrated the correctness of a prediction of the Faraday–

Maxwell theory of electromagnetism. This discovery, one of the foundations

of the modern theory of electricity, made Ro¨ ntgen famous internationally.

By this time he had been at Giessen ten years and was forty-three years old.

He began to receive offers from other universities. One was Utrecht, but,

although Bertha liked the idea of returning to the Netherlands, he turned

Wilhelm Conrad Ro¨ ntgen (1845–1923) 181

it down. Another was to return to Wu¨ rzburg as professor of physics and

director of the new institute of physics, where there was accommodation

for the director in the formof a spacious nine-room apartment. He accepted

the latter position without hesitation and took office on October 1, 1888.

At this age the bearded Ro¨ ntgen was impressive in appearance. As a

colleague wrote:

He had a penetrating gaze and unassuming manner which gave him

extraordinary character and dignity. His nature was amiable and

always courteous, but his reticence and shyness amounted almost to

diffidence when he received strangers. In later years his shyness acted

as a wall; it protected him from selfish and curious persons, but it also

kept many fine and sincere persons away. Occasionally Ro¨ ntgen

would appear distrustful, but actually he concealed a deep sympathy

and understanding. After he was convinced of the sincerity of his

caller he would extend a warm friendliness toward him. He had close

friends among his colleagues at the university who remained close to

him for the whole of his life.

Ro¨ ntgen showed no patience with persons whose behaviour was

actuated by selfish personal motives or was noticeably shaded by

personal prejudices. His was an intellectual honesty which

characterized not only his work but his attitudes as well. He believed

that their attitudes interfered with the progress of science and were

actually detrimental to the person. Many times he was gruff to people

only concerned with their own importance and he was not apologetic

for such behaviour. He detested those who would try to cover up

superficial academic knowledge with dazzling but utterly meaningless

theories.

Ro¨ ntgen disliked lecturing, speaking in such a low voice that students

at the back of the class could hardly hear him at all. As an examiner he

was dreaded. Social activities took on a certain routine: four or five families

from his group of close friends would gather for dinner at one or other home.

Dinners were elegant, with fine white wines and red wines drawn from a

cask. For recreation the Ro¨ ntgens made use of a small log cabin they had

bought some five miles from the city as a base for walks. Unfortunately,

Bertha did not enjoy good health, and their adopted daughter was not strong

either.

Ro¨ ntgen was elected Rector of the University of Wu¨ rzburg, for the

customary year of office, after which he and his wife took an Italian tour,

182 From Ro¨ ntgen to Marie Curie

although normally they always took their summer holidays in the Swiss

Alps. In June 1894, just before they left for Italy, Ro¨ ntgen was conducting a

series of experiments with cathode rays. Many other scientists were interested

in these, so he was anxious to proceed as rapidly as his meticulous

standards would permit. Cathode rays would not penetrate more than a few

centimetres in the air but he discovered a new formof radiation, which was

much more powerful. Helmholtz had predicted that, on the Maxwell theory,

a sufficiently short-wave light-ray should go right through solid materials.

He tested this out on various materials. Lead blocked the radiation entirely,

but other metals let it through. However, what struck him most was that,

when he held up his hand, the screen showed the bones of his hand, encased

in darker shadows. He decided that, although the eye might be deceived, the

photographic plate could not be, and took photographs of the phenomenon.

As was his practice, he repeated the observation over and over again, until

he was satisfied, and within a few weeks he was.

So far the work had been kept secret, but nowR¨ ontgen felt sufficiently

confident to publish his results, albeit in just a small academic journal. The

historic paper he wrote, entitled ‘A new kind of ray’, appeared in time for

him to send out copies to many of the leading scientists in the field on

New Year’s Day 1896. There were sceptics, but R¨ ontgen had a reputation

for careful experimentation. The exciting news of his discovery produced a

flood of messages of congratulation from all over the world. The potential

for applications in medical diagnostics was immediately recognized; the

university made him an honorary doctor of medicine, while the students put

on a torchlight parade in his honour. The Kaiser,Wilhelm II, summoned him

to Berlin, to give a demonstration, and decorated R¨ ontgen with the Prussian

Order of the Crown, Second Class. He declined an invitation to speak before

the Reichstag. This was perhaps the first time that a scientific discovery had,

almost overnight, caused such a sensation and received so much publicity,

to Ro¨ ntgen’s horror. He returned to the scientific investigations that had

occupied him before his great discovery. At first the X-ray pioneers saw no

reason to protect themselves against the effect of the radiation, but before

long some of them began to experience loss of hair and burns, particularly

on the hands.

In 1900 Ro¨ ntgen left Wu¨ rzburg, with considerable reluctance, to

become professor of physics and head of the institute of physics at the

University of Munich. The next year, when Nobel prizes were awarded

for the first time, he received the prize in physics ‘for the discovery of the

remarkable rays subsequently named after him’. Although he always called

Joseph John Thomson (1856–1940) 183

them X-rays, others called them Ro¨ ntgen rays. In his will he left the prize

money to the University of Wu¨ rzburg to be used in the interests of science,

but unfortunately the legacy became valueless together with the rest of

R¨ ontgen’s personal fortune when the German economy collapsed after the

First World War. The Prince Regent of Bavaria bestowed upon him the title

of ‘Geheimrat’ in 1908 and soon afterwards the city council of Weilheim,

where he owned a hunting lodge, made him an honorary citizen. His wife

Bertha, whose health had been failing for some years, died in 1919; the following

year he retired from his position at the university while retaining

facilities in the laboratory of the physics institute. A staunch patriot, he was

deeply depressed by the German defeat and its consequences. Ro¨ ntgen died

of rectal carcinoma at the age of seventy-seven on February 10, 1923, in his

Munich apartment; his ashes were buried with those of his wife and parents.

R¨ ontgen was of the opinion that his discoveries and inventions belonged to

humanity and that they should not in any way be hampered by patents,

licences or contracts or controlled by any one group. His altruism made

a very favourable impression on scientists both in Germany and abroad.

A statue of him was erected on the Potsdam Bridge in Berlin.

Joseph John Thomson (1856–1940)

Manchester in the middle of the nineteenth century was a prosperous industrial

town with an active cultural life. Many of the northern businessmen

were devout nonconformists. Their faith often impelled them to live austere

184 From Ro¨ ntgen to Marie Curie

personal lives and frequently to initiate schemes of social amelioration and

works of personal charity, often at considerable cost to themselves. The

advancement of education, public health and science were the main areas

which attracted these public-spirited men. One of the most important of

these initiatives was Owens College, the predecessor of Manchester University,

founded in 1851 by a wealthy bachelor who had been in the textile

trade. Its aim was to provide an education modelled on the practices of the

Scottish universities, rather than Oxford and Cambridge, and to be of use

to young men who intended to enter commerce or industry. The courses

were based on traditional subjects: Latin and Greek, mathematics, natural

philosophy, English and history, chemistry, foreign languages and natural

history. The degrees were those of the University of London, which imposed

no residence requirement. There were no faculties of law, medicine or

technology.

Joseph John Thomson, later known informally as J.J., was born on

December 18, 1856. His father Joseph James Thomson managed a small

business selling antiquarian books, occasionally acting as publisher as well.

This prospered sufficiently to give him a reasonable living and a house with

servants in the middle-class suburb of Cheetham Hill. The Thomsons had

lived in Manchester for several generations but originally they came from

lowland Scotland – hence the spelling of their name without the letter p.

Joseph married Emma Swindells, who also came from Manchester. She has

been described as small, with bright dark eyes brimming with kindness, and

dark hair hanging in clusters of ringlets over her ears. They had one other

child, Frederick, who was four years younger than J.J.

Although not much seems to be on record about the father, who died

when J.J. was only sixteen, it is recalled that he was acquainted with some

of the scientific and literary people of Manchester, many of whom would

probably have patronised his bookshop. When J.J. was a boy he had been

introduced to the famous Joule by his father, who had afterwards said ‘some

day you will be proud to say you have met that gentleman’. J.J. was a shy

boy but determined and ‘knew which way he was pointing’. When asked

what he wanted to do when he grew up, he replied that he wanted to do

original research, whereupon one of those present tapped him on the head

and said ‘don’t be such a little prig, Joe’. By the age of fourteen he could be

described as a ‘rather pallid, bony youth with the air of a serious but happy

student, unassuming and modest without diffidence, very approachable and

friendly’.

Joseph John Thomson (1856–1940) 185

J.J.’s father seems to have decided that his elder son’s aptitude for

mathematics indicated that engineering would be a more suitable choice of

career for him than bookselling, perhaps hoping that the younger son would

enter the business instead. Since J.J. had completed his secondary education

by the age of fourteen, it was thought that Owens College would fill the gap

until he was old enough to be apprenticed to a Manchester engineering

firm. However, after the early death of his father there was no money to

pay the premium for the apprenticeship; the family business was sold and

his widow, with her two sons, moved to a smaller terraced house nearer

Owens, where J.J. was in his second year. She could only just afford to keep

him there.

After a difficult first twenty years, the college had started to flourish,

despite having rough and overcrowded facilities. The range of lectures in

engineering, mathematics and natural philosophy was impressive. There

was probably nowhere outside Oxford and Cambridge that could match it

in England, though Glasgow was perhaps its equal in Scotland. In effect J.J.

went through university in three subjects while still a schoolboy. After he

left, having thrived on the teaching it provided, the college authorities made

a regulation raising the minimum age of admission.

To complete his education J.J. was determined to go to Cambridge, but

his mother could not afford to send him there unless he won a scholarship.

As there were no entrance scholarships for engineering or physics, the route

had to be through mathematics. He succeeded on his second attempt at

winning a scholarship to Trinity, the college with the highest reputation

and the most difficult to enter as a scholar. There were several reasons

why he chose Trinity. The first was his own self-confidence in his ability;

he did not hesitate to test himself. The second was that a number of his

teachers at Owens had come from the college. Thirdly, Trinity, as we know,

was currently the college of Clerk Maxwell, the first Cavendish Professor,

whose famous treatise on electricity and magnetism was a starting-point

for much of J.J.’s early thoughts about research.

In the course of his long life J.J. never lived anywhere else but Manchester

and Cambridge. Moreover, at Cambridge he was living either inTrinity,

as undergraduate, college fellow, lecturer, young professor or head of the college,

or nearby, and all these homes were within a few minutes walk of each

other and of the Cavendish laboratory, which was then in the town centre.

He liked Cambridge: the air, he said, seemed to favour him. Not once in

that time could he recall a working day lost by sickness. His relations with

186 From Ro¨ ntgen to Marie Curie

his mother had always been close; she was a sweet-natured person, proud

of her son without, apparently, understanding anything of his work. Up to

her death in 1901, he regularly spent part of his summers with her, after his

marriage as well as before, either in Manchester or at some seaside resort,

usually with his younger brother Frederick, who worked for a firm of calico

merchants in Manchester. A lifelong bachelor, Frederick admired his elder

brother’s success; after he retired early due to ill-health he spent the last

three years of his life in Cambridge.

Mathematics was still (at Cambridge, at least) the usual approach to

the study of physics, and the best students had to face the peculiar rigours

of working for the mathematical Tripos. The examination was held in

January in the unheated Senate House; during the midday break J.J. went

to the barbershop for a shampoo. Having been coached, like Strutt, by

the famous Routh, he was listed as second Wrangler, close behind Joseph

Larmor, who spent his life in Cambridge at the adjacent St John’s College.

The two men became life-long friends, though there is little correspondence

between them to show it, mainly because they lived so close and saw each

other so often. In J.J.’s final year as an undergraduate Clerk Maxwell died,

after years of poor health and periods of absence from the Cavendish. It was

a matter of great regret to J.J. that they never met, but was able to acquire

Maxwell’s armchair, and kept it for the rest of his life in his study at home;

much of his physics was done sitting in that chair.

After graduating J.J. stayed on at Trinity to try for a prize fellowship,

which would provide him with seven years of leisure for research. His choice

of subject for his fellowship thesis, on the transference of kinetic energy,

followed on from the inspiring lectures on energy he heard at Owens College.

Three years were allowed for the preparation of such a thesis, but, with

great concentration and application, J.J. completed his within one year and

with characteristic self-confidence submitted it, against the advice of his

tutor. He was successful; the following year he won the Adams prize for a

dissertation on the motion of vortex rings and became assistant lecturer in

the college; in 1883 he became university lecturer as well.

In the three years between his fellowship election in 1881 and 1884,

the crucial year of his early academic career, J.J. published a number of

important papers on physics. These were both theoretical and to a lesser

extent experimental, including – in 1883 – the first paper on the subject he

was to pursue throughout his later life ‘On the theory of electric discharge

in gases’, a new area of research at the Cavendish and one that was to lead

to the discovery of the electron. They made his reputation in what was

Joseph John Thomson (1856–1940) 187

then the small world of professional mathematicians and physicists. In the

first half of 1884, when still under thirty, he was elected a fellow of the

Royal Society.Without that it is doubtful whether a few months later, when

Rayleigh retired from the Cavendish chair, J.J. would have been appointed

to succeed him. As it was the appointment took everyone by surprise. The

fact that he should have put himself forward for the post at all was further

proof of his sturdy self-assurance; only eight years previously he had arrived

in Cambridge as a freshman.

There were nine electors for the chair and at least four of them, in

the previous three years, had directly been involved in adjudicating J.J.’s

work for the Trinity fellowship, the Adams prize or the fellowship of the

Royal Society. In particular, the external elector was SirWilliam Thomson,

no relation to J.J., who, as we have seen, could himself have taken the post

on several occasions if he had so wished. With his commanding reputation

and equally formidable manner of speech, it was probably his support that

swayed the decision in J.J.’s favour. The electors took a bold decision and

backed the original thinker of great promise rather than other candidates

with more proven experience of teaching and experimental work, two of

whom had actually taught J.J. in Manchester.

After the Cavendish laboratory had been started under Maxwell and

consolidated under Rayleigh, J.J. was the right man to develop it further. In

the 1880s physics generally was passing through a quiet period; there were

no grand themes, but a lot of tidying up and improvement of measurements

as well as a very necessary improvement in the methods of teaching and

examining. The number of students at the Cavendish was small, and the

organization of the laboratory informal. It took some time for J.J. to become

established in the post, find promising lines of research and raise the money

to enlarge and equip the laboratory. The professor personally conducted the

administration, including, it seems, the book-keeping. J.J. wrote his correspondence

standing up at a desk with a sloping top, in a neat and legible

handwriting. It was the only thing about him that was neat, since he was

noticeably casual in organizing his paperwork, his timetable and his dress.

Conditions in the laboratory were described as somewhat chaotic.

One of the best-known Cambridge families of the time was that of

Sir George Paget. He came up to Caius in the 1830s to read mathematics and,

after distinguishing himself in the Tripos, switched to medicine because it

would lead to a fellowship at Caius. He had progressed until he had become

Regius Professor of physic, in which role he transformed the teaching of

medicine in Cambridge. He married and had a family of ten children, of

188 From Ro¨ ntgen to Marie Curie

whomseven reached maturity. Among these were the twins Rose andViolet,

who were born in 1856. Unlike her more extrovert sister, Rose grew up to be

intellectual, precise and calmly organized. Although the twins were almost

opposite in character, they remained devoted to each other all their lives.

Rose Paget, who had become a student at the Cavendish shortly

after J.J. had become professor, had no formal qualification in physics at

all, only an intellectual fascination with science, which had been fostered

by her distinguished father, and a determined will. She and J.J. married in

1890; after his mother she was the only woman in his life and the centre

of his affection for fifty years in a marriage of much warmth and mutual

admiration. In the early years they first lived near the centre of Cambridge

and then from 1899 in a large Victorian house with an acre of garden called

Holmleigh, on the other side of the river Cam from the colleges. They had

two children, a son and a daughter: the son, George Paget Thomson, was to

become a physicist of distinction, who shared the Nobel prize in 1937 for

an experimental demonstration of the wave nature of the electron.

By the early 1890s J.J. had come a long way from his Manchester

roots. A star in the ascendant, he attracted the brightest students to the

Cavendish. He had played himself in carefully at the laboratory and, while

continuing the earlier lines of work and teaching of Rayleigh, had found

himself a major field of research in the conduction of electricity through

gases. Within a few years this was to lead him personally to his greatest

discoveries and bring a world-wide reputation to the laboratory. The nature

of cathode rays was then unknown. In 1897 J.J. succeeded in deflecting them

by an electromagnetic field, thus showing that they consisted of negatively

charged particles. He also measured the ratio of their charge to their mass

and deduced that electrons were about two thousand times lighter than

the hydrogen atom. These revolutionary discoveries were announced by

J.J. on April 30, 1897, at a historic Friday evening discourse at the Royal

Institution.

The growth of the Cavendish was also helped by a wise university

regulation allowing graduate students of other universities to enter Cambridge

as research students. In a photograph of the research students at the

Cavendish taken in 1898, as many as nine out of sixteen were from outside

Cambridge. At the same time, a timely change in the regulations of the

Commissioners of the 1851 Exhibition allowed that well-endowed body to

fund science-research scholarships for overseas students. The first to benefit

from this was Ernest Rutherford; while still in New Zealand he had read

everything J.J. had written and decided that this was the man under whom

Joseph John Thomson (1856–1940) 189

he wished to work. It was the start of a long and fruitful collaboration and

friendship, further described in the profile of Rutherford.

It was the magnetic quality of J.J.’s greatness that drew so many of

these brightest minds, and formed a seed-bed that was continually renewed

as established members went off to professorships around the world (ninetyseven

of them altogether, at fifty-five universities) and new students arrived.

For more than twenty years his group of research workers in experimental

physics was easily the most important in Britain, and probably in the world.

It included a formidable list of scientists, both British and foreign, who in

their turn were to make fundamental contributions to science; at least eight

of them won Nobel prizes. Although so much was achieved at the Cavendish

under J.J., it is striking what was not. It was Hertz who proved the existence

of electromagnetic waves, Ro¨ ntgen who discovered X-rays, Becquerel who

discovered radioactivity, and the Curies who discovered radium, none of

whom were directly influenced by J.J.

According to his son George Thomson: ‘in all his theories J.J. liked

to visualize, and for him the mathematics was always merely the language

which described the physical and spatial concepts in his mind. He had no

idea of mathematics dictating the theory.’ He was not good at the physical

handling of apparatus himself; he devised it in his mind and his personal

assistant constructed it and got it working. To quote his son again: ‘He

had the physician’s gift of diagnosis, and could often tell a research worker

what was really the matter with an apparatus that a man had made and

struggled with miserably for weeks.’ His own apparatus was simply designed

and constructed without unnecessary refinement. The phrase ‘sealing wax

and string’ with which a later generation described the Cavendish apparatus

of his day is not a great exaggeration; judged by modern standards there was

something amateurish about it . . . yet this rather odd collection of glass and

brass did in fact play a major part in producing the revolution in physicists’

conceptions of the nature of matter and energy that was about to occur.

J.J.’s own mind, it was said, showed restless mental activity and originality.

The subjects he pursued were for him the most exciting things in

the world, and he communicated this excitement to researchers. Although

most of the people in the Cavendish in his day were working on the conduction

of electricity in gases, there was no attempt to direct research and

quite a few were working on something else. Everyone at the Cavendish

loved his characteristic smile, and felt a certain pleasure on hearing a footstep

that could only be his. Niels Bohr described J.J. as ‘an excellent man,

incredibly clever and full of imagination . . . extremely friendly but it is very

190 From Ro¨ ntgen to Marie Curie

difficult to talk to him’. Rutherford’s first impression of him is recorded in

a letter he wrote to his fianc´ ee: ‘you ask me whether JJ is an old man. He is

just fifty and looks quite young, small, rather straggling moustache, short,

wears his hair (black) rather long, but has a clever-looking face, and a very

fine forehead and a radiating smile, or grin as some call it when he is scoring

off anyone.’

J.J. could be forceful and determined in getting what he wanted for

his own work for the laboratory and for his students, and was always conscious

that he possessed rare intellectual power, yet he was modest about

his achievements. Throughout his written work he took careful account of

what others had done. This showed particularly in the field of cathode rays,

where much work had been done by German physicists. In the great upsurge

of activity following Ro¨ ntgen’s discovery of X-rays there was a good deal of

parallel activity taking place and no doubt J.J.’s discovery that the cathoderay

stream was made up of particles of a smaller order of magnitude than the

atom, and which were universal constituents of matter, would have been

postulated before long by others who were conducting very similar experiments.

The fact is that he was the first to see the profound significance of

these experiments and it took several years to convince others that he was

right. Although J.J. had no gift for languages, he learned enough German,

with the help of his wife who knew it well, to read the German scientific

journals and kept closely abreast of work being done elsewhere, not only

through the journals but also by direct correspondence. In later years he

was out of sympathy with the new physics developed by Bohr, but by that

time he was no longer Cavendish Professor and no harm was done. He continued

to believe that atoms consisted of electrons embedded in a positively

charged sphere, a model long superseded. J.J. was described as ‘a curious link

between the old and new physics. He opened the door to the new physics

but never went through it himself. It was Rutherford who went through the

door that he opened.’

The growth of J.J.’s intellect seems to have been almost complete by

the time he left Manchester. What Cambridge did for him was to supply

the mathematical knowledge, skill and discipline which enabled him to

understand Maxwell’s writings. These profoundly affected him and the

resultant struggle to harmonize the view of the physical universe which

he had formed at Manchester with that of Maxwell led him to the discovery

of the electron. He was assisted in his labours by a comprehensive memory

embracing a great variety of subjects from science to athletic records,

although at times it was liable to fail him and he was known to repeat

Joseph John Thomson (1856–1940) 191

the same story to the same people in a matter of minutes. There were other

instances, not uncommon in the laboratory, which were not capable of an

easy explanation. A researcher would explain to J.J. what he believed was

the theory behind the experimental results he was obtaining: J.J. would

counter this by propounding quite a different view, and the argument would

continue day after day and would finally cease, both sides being unconvinced.

Then, perhaps a month later, J.J. would tell the researcher that he

had found the explanation of the results they had discussed, and would give

a detailed account of the very same theory as that which the researcher had

propounded. The unconsciousness of its origin combined with the more

perfected form was peculiarly trying. If generally this was dismissed as an

instance of the vagaries of great minds, it did from time to time lead to

difficulties and misunderstandings.

Being a man of very varied tastes and interests, often unexpectedly

pronounced or unusual, Thomson was ready to talk to almost anyone about

almost anything, and seemed to be bored by no subject except philosophy,

which he once described as a subject where you spent your time trying to

find a shadow in an absolutely dark room. He was one of the founders of the

Society for Psychical Research and was also keenly interested in telepathy

and water-divining.

The outbreak of the FirstWorldWar in 1914 followed by his election

to the presidency of the Royal Society brought J.J. more into public affairs. As

British scientists made their contribution to the war effort, normal scientific

research ground to a halt. However, the backwardness of Britain in applied

science became all too evident and, as president of the Royal Society, J.J.

led the efforts to persuade the government that something had to be done.

Within the society itself he led the opposition to those who wanted fellows

of German descent to be expelled. In 1918, when the war was over, J.J was

appointed to the Mastership of his college, Trinity. At the same time he

was persuaded to resign the Cavendish chair, and hence the direction of the

laboratory, accepting in lieu a personal research chair with facilities in the

Cavendish. He maintained his interest in physics, but no longer contributed

to it himself. As Master of Trinity he was an effective chairman of college

committees, took a keen interest in the students and particularly enjoyed

watching their sporting activities, although he was never at all athletic

himself.

He was most careless in his attire and appearance, and behaved as

if it was a matter of no interest either to himself or to others. As a ready

speaker with a remarkable command of English, he could, when occasion

192 From Ro¨ ntgen to Marie Curie

demanded, deal with complex, difficult or delicate situations with precision

and tact. Travel as a recreation did not in itself appeal to him much, and in

his prime he travelled little except to receive an honorary degree, a medal or

a prize, or to deliver a prestigious course of lectures, for which he was quite

prepared to cross the Atlantic. In later years J.J. played up his Manchester

background, though he rarely revisited the city. He spoke with a noticeable

Lancashire accent and liked regional dishes such as Lancashire hot-pot. His

robust sense of humour came from the north: in a speech he remarked that

there were two kinds of physicist in Cambridge, those who made discoveries

and those who received the credit for them.

As for honours, apart from the Nobel prize in physics in 1906 for

research into the conduction of electricity by gases, he received the principal

awards of the Royal Society, in particular the Copley medal. He received

a large number of honorary doctorates and was an honorary member of all

the leading scientific academies. He was particularly proud of the Order of

Merit. J.J. was knighted in 1908, but later declined the offer of a peerage,

partly because he did not think himself wealthy enough to sustain the

honour. In fact, he died a wealthy man, but this was through shrewdness

in the management of his investments rather than through exploitation of

any of his discoveries. He was always interested in commercial applications

but did not seek to benefit from them personally. Unlike Lord Kelvin, he

never took out any patents, though the cathode-ray oscilloscope and the

television tube derive directly from his apparatus. In a broader sense

the whole of today’s electronic industry descends from his key discovery

of the electron; no-one could have foreseen the vast range of practical applications

a century later. He died at the age of eighty-three on August 30,

1940, in the Master’s lodgings, after a progressive decline over the previous

four years, and his ashes were buried in Westminster Abbey near to the

graves of other great British scientists. There are portraits of J.J. in most of

the institutions with which he was associated.

Max Planck (1858–1947)

Albert Einstein said of Max Planck ‘Everything that emanated from his

supremely great mind was as clear and beautiful as a great work of art; and

one had the impression that it all came out so easily and effortlessly . . . for

mepersonally he meant more than all the others I have met on life’s journey.’

The creator of quantum theory came from an old-established family of

lawyers, public servants and scholars. One of his ancestors was a pastor

in the south-German region of Swabia who later became a professor of

Max Planck (1858–1947) 193

theology at the Georgia Augusta and one of whose grandchildren became

a jurist, the founder of the German civil code. He and Max Planck’s father

were cousins, the latter being also a distinguished jurist and professor of

law first in Kiel and later in Munich. This ancestry of excellent, reliable,

incorruptible, idealistic and generous men, devoted to the service of church

and state, must be borne in mind if one is to understand the character of the

great physicist.

Max Karl Ernst Ludwig Planck was born in Kiel on April 23, 1858,

the fourth child of his parents. His mother, Emma Patzig of Greifswald,

his father’s second wife, came from a family of pastors. He grew up in a

conservative, cultured family in prosperous Wilhelmine Germany. When

he was nine the family moved to Munich, where he attended the renowned

Maximilian Gymnasium. The mathematics teacher he found particularly

inspiring, learning from him such fundamental ideas of physics as the principle

of conservation of energy. His teachers did not rate him an outstanding

student, rather they praised his personal qualities. When it came to choosing

a profession, he considered philology but eventually decided on physics. He

also became an excellent pianist and found in playing music deep enjoyment

and recreation.

194 From Ro¨ ntgen to Marie Curie

After graduating from the gymnasium, Planck studied for three years

at the University of Munich. There was no professor of theoretical physics

at the university at the time, but there were lecturers who gave him a good

foundation in mathematics and physics. It will be recalled that it was then

the normal practice in Germany for students to spend their first two years at

more than one university. The absence of any examination before the final

one made this system possible. Its obvious advantage was that students had

the opportunity to hear the great professors of their day. Planck migrated

for a year to Berlin, where he heard Helmholtz and Kirchhoff. Helmholtz,

he recalled, did not prepare his lectures properly; the students felt just as

bored as he seemed to be himself. Kirchhoff’s lectures were meticulously

prepared, but his delivery was dry and monotonous.

Although Planck’s doctoral thesis of 1879, on thermodynamics, was

not particularly well received, he was not discouraged. He continued to

study the subject in his Habilitationschrift, which qualified him to become

Privatdozent in 1880, but found that he had been anticipated by Willard

Gibbs. He tried to correspond with Rudolf Clausius on matters related to the

second law of thermodynamics, but received no replies. However, Clausius’

papers on entropy were a major influence on Planck, who later used the

concept of entropy as a bridge into the realm of quantum theory. To make

himself better known in the scientific world, Planck competed for a prize

at the Georgia Augusta in 1887, on the concept of energy, but before he had

completed his essay, for which he was awarded second prize, he accepted an

associate professorship at the University of Kiel. After the death of Kirchhoff

in 1889, the University of Berlin secured Planck for the chair of theoretical

physics, at first as an associate professor but within three years as a full

professor. He owed this rapid promotion largely to the support of Helmholtz.

Planck’s lecturing style was to read verbatim from one of his books; if you

had a copy you could follow it line by line.

Meanwhile Planck’s research into thermodynamics had led him to

the inescapable conclusion that something new was needed; he called it the

quantum of action. Matter, he decided, emits radiant energy only in discrete

bursts; the quantum of energy grows larger as the wavelength decreases,

but the product is constant. Planck had no doubts about the importance

of his idea. He told his son that it was either complete nonsense or the

greatest discovery since Newton. In public, naturally, he was much more

modest, so much so that it was said later that he had not begun to realize its

full implications himself. It is generally acknowledged that the year 1900

of Planck’s discovery marks the beginning of a new epoch in physics, yet

Max Planck (1858–1947) 195

during the first years of the new century it did not make much of an impact.

Planck himself returned to thermodynamics. Personally and scientifically

he was thoroughly conservative and recoiled from his own findings, which

clashed with the tenets of classical physics, and he tried hard to find ways

of reconciling them.

Planck was very much a family man. His first marriage to Marie

Merck, the daughter of a banker, ended in divorce, but he remained on good

terms with her. Their four children lived with their mother until she died

in 1909. He then married again, to a niece of hers, Marga von Hoesslin. The

Plancks lived in Grunewald, an attractive new suburb at the edge of the pine

forest west of Berlin. According to his disciple Lise Meitner, ‘Planck loved

happy, unaffected company, and his home was a focus for social gatherings.

Advanced students were regularly invited to his home . . . if the invitation

fell during the summer semester we played tag in the garden, in which

Planck participated with almost childish ambition and great agility. It was

almost impossible not to be caught by him.’ Later she said that, while she

had been swept along by Boltzmann’s exuberance, she loved and trusted

Planck for his depth of character. ‘He had an unusually pure disposition

and inner rectitude, which corresponded to his utter simplicity and lack of

pretension . . . he was such a wonderful person that when he entered a room

the atmosphere in the room got better.’

When the ‘golden age’ of physics began at the turn of the century,

Berlin was central to its development, as Planck was to its success. Although

he was not in the vanguard of those who accepted Einstein’s ideas, in time

Planck developed the greatest admiration for what Einstein had achieved.

The Berlin Academy, mainly at the instigation of Haber, Nernst and Planck,

created a special chair for Einstein, which allowed him to pursue his ideas

unhampered by teaching and routine work. For many years Planck and

Einstein met at regular intervals; their collaboration made Berlin, in the

years preceding the First World War, the leading centre for theoretical

physics in the world. A friendship that went far beyond the exchange of

scientific ideas developed between them. They shared a fascination with

the secrets of nature, similar philosophical convictions and a deep love of

music. They often played chamber music together, Planck at the piano and

Einstein on the violin.

Planck was a pianist of great technical ability, who could play at

sight almost any piece of classical music. He also liked to improvize on a

given theme, such as an old German folk-song; at one time he had thought

of becoming a composer (he composed songs, conducted an orchestra and

196 From Ro¨ ntgen to Marie Curie

accompanied the famous violinist Joseph Joachim). One year a large harmonium,

with numerous keys, built at the suggestion of Helmholtz and tuned

harmonically, was delivered to the department of physics. Planck learned

to play this complicated instrument and compared the just intonation with

the normal equal temperament. Unexpectedly, he found that our ears prefer

the latter.

When Boltzmann died in 1906, Planck was invited to succeed him in

Vienna, but colleagues in Berlin persuaded him to stay. He served as Rector

of the university for 1913/4; when the war began he was one of a number of

prominent German signatories to the chauvinistic ‘Manifesto of the 93’ or

‘appeal to the cultured peoples of the world’. Like others he soon regretted

doing so, explaining that he had not read it when he signed it. Within the

Berlin academy, of which he was an influential member, he succeeded in

preventing the expulsion of members from enemy countries.

Planck was deeply rooted in the traditions of his family and nation,

an ardent patriot, proud of the greatness of German history and typically

Prussian in his attitude to the state. During the war years, however, a change

came over him. It was not only the general suffering, the catastrophic end to

the struggle which hurt his patriotic feelings deeply, but grievous personal

loss. Three of the four children of his first marriage died during the war

period. His eldest son Karl was killed in action on the western front in 1916.

The two daughters, Emma and Margarete, were identical twins; Margarete

died in childbirth; her sister took charge of the baby and then she too died

in childbirth. The surviving children were brought up by their grandfather.

Only one son, Erwin, of the first marriage remained, and a younger son,

Hermann, of the second marriage. Erwin also fought in the war; he was

taken prisoner by the French but survived.

In 1928 Planck, being seventy, retired from his university post, but

continued in office as permanent secretary of the Berlin Academy and as

president of the Kaiser Wilhelm Gesellschaft, the Society for the Advancement

of Science. In the Wilhelmine period the prestige of chemistry in

Germany was very high, so, when it was proposed that the society create

a number of specialized research institutes, financed at first by German

industry, later with increasing support from the state, it was decided that

the first two should be for chemistry and for physical chemistry. The physics

institute was not organized until after the First World War, when Einstein

was appointed the first director. The Society fully intended that it should

become a proper institute with a building including a laboratory, but at first

it was no more than an office concerned with dispensing research grants.

Max Planck (1858–1947) 197

The Rockefeller Foundation was prepared to help finance the building of a

laboratory if the Germans assumed responsibility for its maintenance. This

was a project close to Planck’s heart and in 1938 he had the satisfaction of

seeing the long drawn out negotiations concluded. However, by then the

golden age of German science was over. We must go back over the previous

decade to understand what had happened.

In 1929 the worldwide economic collapse was under way; in

Germany unemployment began to soar. Reactionary groups in Germany

never accepted the reality of the defeat of the imperial military machine

and sought to exploit a historical fantasy in which an undefeated army

was betrayed by a sinister alliance of socialists and Jews. The reactionary

forces included not only remnants of the military, industrialists and large

landowners, but also many conservative academics. They all detested the

social-democratic government of theWeimar republic and were dedicated to

its destruction, the generals and business magnates by overt action and the

university mandarins by incessant and insidious propaganda. Against this

background the Nazis were gaining more and more adherents, and there

were demonstrations on the streets of Berlin, in which students were much

involved. The summer of 1932 marked the beginning of the end for the

Weimar republic: by January 1933 Hitler was Chancellor and soon effectively

dictator. Many Germans wrongly believed that, having achieved

power, Hitler would moderate some of the more extreme Nazi policies;

they regarded Nazism as a passing phase and Hitler as a puppet in the

hands of the Reichswehr and the great industrialists. One has to remember

that even many highly educated Germans never took the Nazi movement

seriously. When they began to realize its disastrous impact it was too late

for any serious opposition.

The first three months of the Third Reich began with an attack on

Jewish and left-wing intellectuals and members of the cultural elite, such

as musicians, artists and authors. Jewish businesses were boycotted.Within

Prussia all Jewish judges were dismissed. This action was followed by much

more far-reaching legislation ‘for the reconstitution of the professional civil

service’ to ensure loyalty to the new regime. Its purpose was to exclude

from state and municipal service ‘unreliable elements’, socialists and other

political opponents as well as Jews. ‘Non-Aryan’ included ‘descended from

non-Aryan, particularly Jewish, parents or grandparents. It suffices if one

parent or grandparent is Jewish.’ The rules made exceptions for those who

had fought in the First World War but in practice the only effect was

to delay their dismissals. Similar action was taken against socialists and

198 From Ro¨ ntgen to Marie Curie

communists, but in scientific circles it was the Jews who were most affected.

The act also applied to Privatdozenten, who were stripped of their venia

legendi. Four years later people with Jewish spouses were included.

The law applied to the teaching staffs of universities and technical

institutes, since in Germany they are state employees. In 1933, as a consequence,

approximately 1200 academics were dismissed, without notice. Of

course the law also meant that many younger people who were hoping for

academic positions were prevented from obtaining them, while older people

had to decide what to do. Those who were not affected by the new law felt

it useless to protest. Some even took advantage of the resulting vacancies to

advance their careers. The students, many of whom were Nazi supporters,

contributed by organizing the burning of books by Jewish authors. Ordinary

people were astonished at the speed and intensity of it all; the course of

events was so bizarre and irrational that they could not believe it was

happening. Although anti-Semitism of a less-virulent form had existed in

Germany before Hitler, not only under the empire but even under the

Weimar republic, nothing like Nazi anti-Semitism had been seen before.

Planck’s reputation as diplomat, patriot and conciliator, and his professional

standing, meant that he was themantowhomthe scientists looked

for leadership. Universally respected for his absolute integrity and devotion

to German science, Planck went to see Hitler in 1933, to plead for reason

and restraint, emphasizing the enormous damage being done to science in

Germany by the racist laws. Characteristically, Hitler worked himself into

such a rage that Planck could do nothing but listen in silence and take his

leave. Afterwards Heisenberg said he looked ‘tortured . . . and tired’. Hitler

had assured him, Planck said, that the government would do nothing further

that could hurt science in Germany. Planck trusted that the violence and

oppression would subside in time. ‘Take a pleasant trip abroad and carry on

some studies’, he advised a worried colleague, ‘and when you return the

unpleasant features of our present government will have disappeared.’

The logical process of German thinking inhibited resistance. ‘If I protest’,

the reasoning went, ‘I shall be removed frommypost where I have influence,

then I’ll have none. So I had better be quiet and see what happens.’

The Prussian tradition of service to the state and allegiance to the

government was deeply rooted in Planck. Whatever his personal feelings,

he believed that it was his duty to work with the regime; he did not believe

that public protest would achieve anything. Busts of Hitler were installed in

the institute. Telegrams were sent to Hitler avowing pride in the ‘national

resurrection’ which was taking place and thanking him for his ‘benevolent

William Henry Bragg (1862–1942) 199

protection of German science’. When Einstein, under pressure, resigned

from the Berlin Academy, Planck wrote to thank him for doing so and hoped

that they would remain friends. For the next ten years Planck, like other

German scientists, omitted all reference to Einstein when relativity and

quantum theory were under discussion, believing that it was more important

to promote his work than to credit him with it, which might have led

to political interference.

By 1938, far from relaxing, the Nazi persecution of the Jews had

reached a new pitch of intensity. The admission of Jews to higher education

was already very restricted; now it was forbidden. Thoroughly disillusioned,

the eighty-year-old Planck resigned as secretary of the academy in 1938,

after twenty-six years of service. He still enjoyed good health, due to the

simplicity and regularity of his life and his custom of spending most of his

holidays in the Bavarian Alps, usually at a small property he owned near

Tegernsee. When he lectured it was usually on science and religion.

After the Second World War Planck was but a shadow of his former

self. His house in Grunewald had been destroyed in one of the air raids on

Berlin, and he had lost all his possessions. His son Erwin, the only surviving

offspring of his first marriage, was marginally involved in the bungled

July 1944 plot to assassinate Hitler led by Count von Stauffenberg and was

executed by the Nazis. Towards the end of the conflict the Plancks took

refuge on the estate of a friend on the west bank of the river Elbe, near

Magdeburg. There they found themselves between the lines of the retreating

Germans and advancing Allied armies; the battle raged around them

for days. Eventually the American troops came and took him to safety in

Go¨ ttingen, where he remained, leaving on only a few very special occasions.

A great celebration was being prepared for his ninetieth birthday but a few

months previously his health had begun to fail and he died from a stroke

on October 4, 1947. Max Planck had received the Nobel prize for physics in

1919, for his discovery of energy quanta, and other honours too numerous

to mention.

William Henry Bragg (1862–1942)

The early life of William Bragg, the founder of the science and art of

X-ray crystallography, was tough and testing. He wrote about it in a short

autobiography in 1927, not intended for publication, and as a result we have

more information about these years, before he arrived in Australia, than

we have for many other scientists of his period. Since his son was also an

200 From Ro¨ ntgen to Marie Curie

eminent physicist and his first name was also William, we must be careful

to distinguish between them.

The Bragg family came from West Cumberland, the part of England

that lies between the Lake District and the Solway Firth. William Henry

Bragg was born on July 2, 1862 at a farmhouse called Stoneraise Place near

the market town ofWigton. His mother, MaryWood, was the daughter of the

local vicar. He did not remember her well, for she died in 1869 at the age of

thirty-six when he was barely seven years old. His father Robert John Bragg

had taken up farming after retiring from the merchant marine. He lived on,

but there is little about him in the autobiography. William, the first-born

child, grew to manhood with hardly any parental love or guidance that he

could recall. Instead his boyhood was dominated by an uncle, also named

William Bragg, with whom he went to live after he had lost his mother.

Uncle William was a pharmacist at Market Harborough in Leicestershire,

a widower with no children of his own. His nephew recalled that ‘there

were no parties for children; we never went to other people’s houses, and

no children came to ours. I think my uncle was too particular. He used to

lecture us terribly, talking by the hour, and I suspect he was not to be shaken

in his opinions by anyone.’

William Henry Bragg (1862–1942) 201

School offered some outlet from this regime. On the initiative of

UncleWilliam the old grammar school at Market Harborough was reopened

the same year as his nephew arrived. The master ‘was an able man, I

believe, . . . and I got on quickly enough’. In 1873, at the age of eleven, Bragg

went up for the Oxford Junior Local Examinations at Leicester and was the

youngest boy in the whole country to pass, despite failing church history

and Greek. An aptitude for mathematics and modern languages rather than

the subjects of the old classical syllabus was already becoming apparent.

The few organized school ball-games were ‘a great delight’ to him,

and there were some happy times with his cousin Fanny, who also lived

with UncleWilliam. Otherwise, whatever enjoyment, satisfaction and contentment

the young Bragg found in life were discovered primarily within

himself. He was already a solitary child: ‘I liked peace and was content

to be alone with books or jobs of any sort.’ However, he was not without

personal ambition; his tough childhood had made him self-reliant, quietly

self-confident and self-content, these characteristics would sustain him for

the rest of his life.

Uncle William would have liked his nephew to go to Shrewsbury, an

old-established public school of good repute, but ‘In 1875 my father came

to Harborough and demanded me; he wanted to send me to school at King

William’s College on the Isle of Man, where his brother-in-law was a master.

I think he became alarmed lest he should lose me altogether.’ The few

accounts of this college in the second half of the nineteenth century do not

paint an attractive picture. The discipline was strict, the social and psychological

pressure severe. Cruelty among the boys was widespread, engendered

no doubt by the fearful beatings that the masters meted out to their pupils.

Bragg survived and even prospered in this environment by adhering

strictly to the rules of the college, by applying himself diligently to his studies,

by enjoying to the full the sporting, social and educational opportunities

that the school increasingly provided, and by repressing almost totally the

emotions he had already learnt to hide. Bragg found much satisfaction in his

school work, especially the mathematics, where his school reports testify to

his exceptional ability and achievements. In 1880 he won a school prize for

mathematics, which took the formof Clerk Maxwell’s two-volume treatise

on electricity and magnetism. Outside the classroom, Bragg was first prefect

and then captain of the school. He participated in many activities, especially

the annual theatricals of the Histrionic Society. The ultimate academic goal

for school and boys alike was to win a scholarship at one of the Oxford

or Cambridge colleges. In 1880 Bragg won a minor scholarship to Trinity

202 From Ro¨ ntgen to Marie Curie

College, Cambridge. The following year he tried again in the hope of upgrading

it to a foundation scholarship, but his academic work had stagnated and

he did not succeed: ‘The effective cause for my stagnation was the wave of

religious experience that swept over the upper classes of the school during

that year. The storm passed in time, sheer exhaustion, and the fortunate

distraction of other things, work and play.’

Bragg went up to Cambridge in 1881. To begin with he was lonely:

‘I had no companions’, ‘I could not afford, or thought I could not afford,

to join the Union or the Boating Club.’ His carefulness and reserve held

him back. He was coached, like Strutt and J.J. Thomson before him, by the

famous Routh, an indication of Bragg’s own awareness of the Cambridge

scene and of Routh’s early appreciation of his abilities. In the college examinations

of 1882 he won a prize and his minor scholarship was converted

into a foundation scholarship, which brought him various small privileges.

When he took the first part of the Tripos in 1884 he came out, to his great

joy, as thirdWrangler. For the second stage he specialized in physics, gaining

some experience of experimental work. When he gained first-class honours

in the examination at the beginning of 1885, he might have tried for a fellowship,

but there happened to be strong competition that year. Instead

he started experimental work in the Cavendish Laboratory and by the

end of that year he knew Thomson pretty well. Although earlier he was

‘much shut in myself, unventuresome, shy and ignorant’, after graduation he

‘found Cambridge a lovely place and Trinity something to be very proud to

belong to’.

Walking along King’s Parade to the Cavendish one morning, Bragg

was joined by Thomson, who started to talk about the professorship of

mathematical physics at the University of Adelaide in Australia, which had

just been advertised; Horace Lamb, the incumbent, was moving to Owens

College in Manchester. When Bragg enquired whether he might have a

chance, Thomson said that he might. Bragg applied by telegraph, only just

in time. In fact there was a strong field of 23 candidates; by far the ablest

man was excluded ‘on personal grounds’ (not safe with the bottle). After the

interviews, which were held in England, Lamb reported the conclusion to

the Chancellor of Adelaide: ‘yesterday the interviews were held and – with

some slight hesitation between two of the candidates – we unanimously

recommend Mr Bragg of Trinity College, Cambridge. It is evident that his

mathematical abilities are of the highest and he has also worked at physics

in the Cavendish Laboratory under my coadjutor in the appointment, who

says his work is very good . . . as far as I can judge the only possible source

William Henry Bragg (1862–1942) 203

of misgiving as to the propriety of our choice is Mr Bragg’s youth, he is

only 23.’

That evening at Market Harborough a telegram broke the exciting

news that he had been chosen. UncleWilliam broke down and wept (Bragg’s

father had died shortly before). The position was a professorship, where he

would be his own master, with a generous salary, and there was all the

excitement of going to a new country. The colony of South Australia had

been founded only in 1836, but Adelaide was already a fine city of some

30 000 inhabitants; and the university had already been in existence for ten

years.

Soon after his arrival in Australia Bragg found time to explore the

country to the east of Adelaide as far as Melbourne and Sydney before settling

down to work. The problem in Australian universities during this

period was neither shortage of money nor conservatism of thought but rather

a shortage of students who wanted to study and who could afford to do so.

The university capped the educational pyramid but the base of the pyramid

was weak. Bragg found himself heavily overworked; the full extent of the

demands on his time and physical stamina was something he had not foreseen.

Consequently, although he followed new developments in science, he

was not involved in research at all at this stage in his career.

One of the leading citizens of Adelaide at this time was Charles

Todd, the government astronomer, postmaster-general and superintendent

of telegraphs, famous throughout Australia as the architect and builder of

the transcontinental telegraph line, which was one of the epic achievements

of Australian history. It linked the eastern cities of the country through

Adelaide with Darwin on the north coast and then by submarine cable with

the outside world. It was after Todd’s wife Alice that the town of Alice

Springs was named. Bragg had met Gwendoline, one of the Todd daughters,

several times at their home in the Adelaide observatory. When the family

went on holiday to Tasmania, he accompanied them, proposed marriage to

Gwendoline and was accepted.

Despite the heavy pressure of work at the university there were

ample opportunities for recreation in Adelaide. Bragg performed in amateur

dramatics, played tennis, golf and lacrosse, and took up the new craze of

bicycling. Gwendoline was keen on painting and performed in Gilbert and

Sullivan operettas; together they had a busy social life. In 1897 he took her

on her first visit to England, and it was after their return that he started to

think seriously about scientific research – it had never before entered my

head, he once remarked. He was particularly interested in Marie Curie’s

204 From Ro¨ ntgen to Marie Curie

work on the element radium, of which he was able to purchase a sample,

and began experimenting with it. He sent his results to Rutherford, the

great authority on radioactivity, and received an encouraging reply. Before

long he was being asked whether he might be interested in moving closer to

the mainstream of scientific research. Because Rutherford was leaving for

Manchester, a possibility opened up at McGill University in Montr´ eal, but

nothing came of this.

After Bragg had been elected fellow of the Royal Society in 1907, he

received and accepted an invitation to become professor of physics at the

University of Leeds, not far from Rutherford at Manchester. So now life,

work and interests in Adelaide had to be wound up. He had enjoyed success

there, success in university teaching, in popular lectures, in sport, in

adult education; he was a highly respected citizen, governor of the public

library, museum and art gallery, a pillar of his parish church, on the council

of the school of mines and prominent in the Australian Association for the

Advancement of Science. The family said goodbye to Adelaide at the beginning

of 1909. They now had two adolescent children, William Lawrence,

the future physicist, his brother, Robert, and a toddler named Gwendoline

like her mother. They soon began to regret what they had left behind in

Australia, where they loved the life.

For Bragg himself there was a warm welcome by his new colleagues

in Leeds although the students did not appreciate his lectures. He became

engaged in a tiresome dispute with Charles Groves Barka, then professor at

King’s College, London. It boiled down to the old disagreement on the nature

of light between the corpuscular theorists on the one hand and the undulatory

theorists on the other. In research he continued to study radioactivity,

especially the passage of alpha and beta particles and gamma rays through

matter. In 1912 he invented the Bragg diffractometer for the measurement of

X-ray wavelengths and with his son discovered the law of X-ray diffraction.

For Gwendoline initially the contrast between beautiful Adelaide and

the dirty industrial city of Leeds, with its rows of poor little back-to-back

houses, was quite painful, with only the wild open country to the north to

provide relief. Before long, however, she had a house of her own, a pleasant

square house with low-pitched slate roof and large garden, with carriage

sweep and lawn. She employed two maids and a cook, and began to build

up a social circle, including some of the successful manufacturers of the

city, the brewers and the steel-makers, the makers of railway engines and

of ready-made clothing. She threw herself into social work, together with

the wives of such people.

William Henry Bragg (1862–1942) 205

For Bragg struggling at Leeds there was some compensation in the

success of his eldest son Lawrence, who was doing brilliantly at Cambridge.

Later a certain tension grew up between them. Unlike his father, Bragg junior

held to the undulatory theory of light. Even after they had shared a Nobel

prize in 1915, for their analysis of crystal structure by means of X-rays, this

tension persisted, although it never seemed to disturb their mutual affection.

They collaborated on a book, X-rays and Crystal Structure, published

in 1915. When their research overlapped, Bragg senior never hesitated to

give credit to ‘his boy’. Bragg senior was always scrupulously fair in giving

credit to his son’s contributions to their joint work, yet it was assumed by

others that the father was just showing parental generosity and that he was

really the dominant contributor. Again, when his son first used a Fourier

synthesis to calculate the electron density in a crystal in an important paper

in 1929, he acknowledged that this work owed much to a suggestion put

forward by his father much earlier, but later came to feel that the paper

should have been a joint one.

In 1915 William Bragg moved from Leeds to London as Quain

Professor of physics at University College and became involved in research

on underwater sound propagation for the admiralty. After the war he tried

to build up a research group at the college, but he did not care for the way

the place was run. However, early in 1923 the death of the aged Sir James

Dewar, the director of the Royal Institution, created an opportunity for him

to move to somewhere more congenial. According to the then secretary of

the Institution, Dewar had hoped that Rutherford would be his successor.

‘So one day when Rutherford had come from Cambridge to give a lecture

at the Royal Institution we interviewed him. He explained that he was

too deeply committed at Cambridge to think of changing. “But”, he said,

“I know of a man who is as well fitted as I am to fill the billet.” We eagerly

asked the name of this man: “William Bragg”, he replied. I supposed he

meant young William Bragg [i.e. the son Lawrence]. “No”, he answered,

“I mean Sir William Bragg, professor of physics at University College,

London; he is a great man of science and also a very great man”.

When the invitation arrived, on May 7, 1923,William Bragg knew that

he would be given the facilities he needed for his own research in the Davy–

Faraday Laboratory. Moreover, he had always worked for an understanding

between science and the other disciplines, and he would have plenty of

scope to pursue this through the noble tradition of public lecturing. Already

in 1920 he had given the Christmas Lectures intended for children on ‘The

World of Sound’. An excellent lecturer himself, he explained that, in his

206 From Ro¨ ntgen to Marie Curie

view, ‘the value of a lecture is not to be measured by how much one manages

to cram into an hour, how much important information has been referred

to, or how completely it covers the ground. It is to be measured by how

much a listener can tell his wife about it at breakfast the next morning . . .’

He particularly felt that it was quite wrong to read a lecture: ‘I think it is

a dreadful thing to do, something quite out of keeping with everything a

lecture should mean. When a man writes out a lecture he invariably writes

it as if it were to be read, not heard. The ideas follow each other too fast. It

is easy for the lecturer to deliver well-considered rounded phrases but the

audience has to follow and to think.’

However, the Royal Institution was very run down, most of the scientific

staff were past their best, and it would take energy and determination

to restore it to its former glory. William Bragg set to work energetically,

and within a year the place had been transformed. Rutherford as visiting

professor was often in the laboratory. Gwendoline played her part by

entertaining in the Upper Chambers. While they were at Leeds the Braggs

had rented a country cottage in beautiful Wharfedale, above Bolton Abbey.

Wharfedale was now too far away but they found a romantic old place called

Watlands near Chiddingfold in Surrey, within easy reach of London, to

provide a retreat from the official residence of the director.

William Bragg had been knighted in 1920; now a different honour

arrived, the prestigious Copley medal of the Royal Society, and a stream of

other scientific distinctions. Sadly, Gwendoline’s health was giving cause

for concern and she died in the autumn of 1929. Sir William was not yet

seventy, but he tended to get very tired, although determined to carry on.

He would walk to the Royal Society at Burlington House from the Royal

Institution in Albemarle Street, just a few hundred yards, with his old slow

countryman’s walk, making several pauses on the way when he seemed

to be taking an interest in some shop window. One evening, opening his

study door, his younger daughter noticed how wearily he looked up from

his papers: ‘Daddy’, she cried, ‘need you work so hard?’ He answered simply

‘I must my dear; I am always afraid they’ll find out how little I know.’ In

1935 he was elected president of the Royal Society; he had to be persuaded

that at seventy-three he was not too old for this.

Although Sir William was not attracted by politics – he declined an

invitation to stand for Parliament – he made an influential radio broadcast,

putting the case for what he called ‘moral rearmament’. This phrase was

taken over by the American evangelist Dr Frank Buchman, leader of the

Oxford Group, but Sir William was no follower of his. When the Second

William Henry Bragg (1862–1942) 207

World War began, Sir William was involved in various kinds of committee

work. He had always been keen on broadcasting about science; one of his last

contributions was to a radio programme on ‘The Problem of the Origin of

Life’. A few days after that he took to his bed and on March 12, 1942 he died,

at the age of seventy-nine. The memorial service was held in Westminster

Abbey.

Lawrence Bragg has already been mentioned briefly; he was scarcely

less distinguished than his father, with whom he shared a Nobel prize. He

might well have had a profile of his own, but he had a much easier start

in life than his father. His story begins in Adelaide, where he was born on

March 31, 1890. At the age of eleven he started school there until four years

later his father decided he was ready for university. At the University of

South Australia he read mainly mathematics, graduating with first-class

honours in 1908 at the age of eighteen. That was the year that the family

returned to England, and it was to be fifty years before he saw the land of

his birth again.

Following his father’s example, Lawrence Bragg went up to Trinity

College, Cambridge, to read mathematics, but moved to physics at the first

opportunity. By 1914 he had been elected fellow and lecturer at Trinity.

When the war came he joined up and was commissioned at once, on the

strength of some previous military experience. He was soon sent to France

where he helped to perfect the French technique of locating enemy guns

acoustically. The award of the joint Nobel prize in 1915 came as he was

setting up an acoustic-ranging station near the front line; his military service

brought him decorations and promotion to the rank of major. His younger

brother Robert also joined up but died in the ill-fated Gallipoli operation to

try to obtain control of the Dardanelles.

As the war drew to a close, Lawrence Bragg was looking for a professorship.

After returning briefly to Cambridge, he was appointed to succeed

Rutherford at Manchester. At the age of twenty-nine he had no previous

experience of teaching undergraduates, although he had a gift for lecturing.

However, the students were mainly ex-servicemen who had no mercy on

novices. Also, a junior staff member sent him anonymous letters accusing

him, amongst others, of incompetence. However, in 1921 he was elected to

the Royal Society and, during the same year, he married Alice Hopkinson,

whom he had first met at Cambridge. Had she not been a native Mancunian

he would have had misgivings about bringing a lively young wife to grimy

Manchester and introducing her to his sober colleagues. However, she

already knew the city well because her father had been a much-loved

208 From Ro¨ ntgen to Marie Curie

physician there. In all respects it was a successful marriage, with four children,

namely two sons and two daughters.

By 1929 he was thinking of moving on. He sounded Rutherford out

about the Cavendish chair, with no result, and was offered one at University

College, London, which he turned down. Worried that he might find himself

remaining in Manchester for the rest of his career, he suffered a nervous

breakdown, but soon recovered. In 1935 he spent a term at Cornell University

in the State of New York and ended the year by giving the Christmas lectures

at the Royal Institution, on the subject of electricity. Then, in 1937, he

was appointed director of the National Physical Laboratory, at Teddington,

on the outskirts of London. He was just reconciling himself to a life of

tedious committee work when, following the death of Rutherford, he was

elected the next Cavendish Professor.

So Lawrence Bragg and family moved to Cambridge after all, and he

ran the Cavendish from 1938 to 1945; for part of the time he was president

of the Institute of Physics as well. Once the Second World War began his

main preoccupation was to see what contribution he could make to the

war effort, not just in Cambridge but nationally. He was knighted in 1941

and became known as Sir Lawrence, his father being Sir William. He had

held a non-resident chair at the Royal Institution since 1938 and in 1953 he

accepted the offer of the much more important post of resident professor. In

spite of his father’s efforts there were still serious financial problems at the

institution and a need for further reform. Sir Lawrence set to work to put

matters right, especially on the research side, and to continue the tradition

of first-class public lectures. In 1966, when he retired at the age of seventysix,

he received the Copley medal from the Royal Society and was made

a Companion of Honour. After retirement he continued to live in London

most of the year, giving lectures at the Royal Institution and elsewhere. He

died in hospital near his home in Waldringfield on July 1, 1971, at the age

of eighty-one.

Marie Curie (1867–1934)

The name of Marie Curie is as well known to the general public as that

of Charles Darwin, Albert Einstein or Louis Pasteur. She was born in

Warsaw on November 7, 1867 and christened Maria. Her parents came

from the numerous class of minor Polish landowners. Her father Wl_adisl_aw

Skl_odowski, a kindly, erudite man, who had studied at the University of

St Petersburg, was a teacher of physics; her mother Bronisl_awa (n ´ee Boguska)

conducted a private school for daughters of upper-middle-class families.

Marie Curie (1867–1934) 209

Their five children were Sofia, Jo´ zef, Bronis_lawa, Helena, and finally Maria

Salomea, the subject of this profile. By the time she was born her father was

professor of mathematics and physics at a high school for boys. However,

Poland was under Russian oppression and, under a policy of replacement of

Polish officials by Russians, he lost his position and the apartment which

went with it. Not without difficulty, he found another apartment where he

could lodge boys of school age and give them tuition.

Her unfortunate father had made the mistake of investing his life

savings in a business owned by his brother-in-law, which went bankrupt.

From then on the family lived in a state of considerable poverty, but there

were other troubles. Her eldest sister Sofia died of typhus. Her mother had

developed symptoms of tuberculosis after her last pregnancy. She resigned

her headship and spent a year ‘taking the cure’, first in the Austrian alps,

then in the south of France, but the disease progressed and she died two

years later. In the aftermath of the loss of her mother, Maria’s health began

to suffer; and she experienced some kind of nervous breakdown. At the age

of fifteen, she was sent off for a year to some country relatives to recover,

being forbidden to study, except that she was allowed to learn French.

210 From Ro¨ ntgen to Marie Curie

Under Russian subjugation, Poland was intellectually isolated.

Conventional universities were not open to women. She joined a selfimprovement

society called the floating university. Maria’s brother J ´ ozef

was studying medicine; her two sisters were planning to go into teaching,

while Maria herself started work as a governess. Her first such post was

a failure but the second was less so. As well as educating the ten-year-old

daughter of her employer, a wealthy lawyer, she started a school for peasant

children and continued her own education by reading, with an inclination

towards science. She had an affair with the son of the house; marriage was

out of the question because of the difference in their stations in life. She

returned to Warsaw and the floating university at the age of twenty. After a

year in the capital working as a governess, she returned home to her father,

who had reluctantly become director of a reformatory near Warsaw. Meanwhile

her elder sister Bronisl_awa, now married, urged Maria to join her in

Paris. In 1891, after some delay, she set off to study at the Sorbonne at the

age of twenty-four.

Marie, as she now called herself, spent the first few months of her

new life staying with her sister and brother-in-law, who had set up a medical

practice in the outer suburbs of Paris. Although she was too hard up to

become involved in the gay social life of fin-de-si`ecle Paris, she then rented a

garret apartment near the university like many other students. She attended

lectures in the physical sciences, but at first she had difficulty with the language,

also she lacked the basic mathematics. However, she persevered and

graduated with high honours first in physics in 1893 and then in mathematics

the next year. She spent the intervening long vacation back in Warsaw,

where she was awarded a scholarship for outstanding students who wished

to work abroad; characteristically she repaid the scholarship money as soon

as she could.

In the spring of 1894 she met Pierre Curie at the home of a Polish

physicist who was staying in Paris. Her future husband was responsible

for the laboratory of the Ecole Municipale de Physique Industrielle et de

Chimie, a new foundation where the lectures were combined with substantial

experimental work. He was tall with auburn hair and sported a small

pointed beard. ‘He seemed to me very young, though he was at that time

thirty-five years old’, she recalled, ‘I was struck by the open expression on

his face and by the slight suggestion of detachment in his whole attitude.

His speech, rather slow and deliberate, his simplicity and his smile, at once

grave and youthful, inspired confidence.’ The son of a homeopathic physician,

he was as shy and introverted as she was. After their first meeting she

Marie Curie (1867–1934) 211

noted that ‘he expressed the desire to see me again and to continue our conversation

of that evening on scientific and social subjects in which he and I

were both interested and on which we seemed to have similar opinions’. He

was dedicated, she soon learned, to a life entirely devoted to science and the

rewards its purity has to offer. He presented her with a copy of an important

paper he had written ‘On Symmetry in Physical Phenomena: Symmetry of

an Electric Field and of a Magnetic Field’. Pierre Curie was a physicist of the

first rank, a pioneer in the investigation of the magnetic properties of various

substances at various temperatures. He discovered the piezo-electric

effect and showed that ferromagnetism reverts to paramagnetism above a

certain temperature (the Curie point). Even in his lifetime, his discoveries

had widespread application, and the fame of this underpaid, overworked

scientist spread far beyond the borders of France, particularly to Britain.

Quite soon after their first meeting, Pierre broached to Marie the

question of marriage. He suggested they might start living together, but

she had been too strictly brought up to consider that. Then he found an

apartment in the Latin Quarter that could be subdivided into two parts;

she said no to that too. However, at least she agreed to his suggestion of a

visit to his parents. He took her to their home in the attractive township of

Sceaux, whose inhabitants had once served a fine Louis XIV chˆateau and its

magnificent park, and which by this time was one of the southern suburbs

of Paris. Dr Eug`ene Curie’s serene, plant-covered cottage stood in the rue de

Sablons, later to be renamed after his famous son. His wife Sophie-Claire

(n´ee Depouilly) bore two sons, Jacques in 1855 and Pierre in 1859. The

radical politics and anticlericalism of the doctor, a former Communard,

appealed to her. Later, when she desperately needed it, the understanding

which developed between them was to be of great importance.

Marie and Pierre Curie were married at a civil ceremony in Sceaux

town hall in 1895. Since Pierre was a freethinker, like his father, and Marie

had given up her faith, they dispensed with a religious ceremony. Her married

elder sister was already in Paris; her father and younger sister came

over fromWarsaw for the occasion. Among the wedding presents the couple

received were two bicycles; in the years to come they took cycling holidays

in Auvergne, the Cevennes and along the coast of Brittany.

The young couple had few distractions from their scientific work;

a bicycle outing or a rare visit to the theatre were their only recreations.

His parents and her elder sister and brother-in-law seemed to be their only

social contacts. She became pregnant, with accompanying sickness, and in

due course gave birth to a daughter, Ir `ene. She felt lonely and homesick

212 From Ro¨ ntgen to Marie Curie

for Poland. After Pierre’s mother had died of breast cancer in 1897, his

father helped the young couple look after the baby. Marie was studying

for the agr´egation, the certificate which would permit her to teach in a secondary

school for girls. She also helped Pierre prepare his teaching courses

while filling in gaps in her scientific education. The Ecole de Physique et

de Chimie agreed that she could start research alongside her husband, on

how the magnetic properties of various tempered steels varied with their

chemical composition.

After Ro¨ ntgen had discovered X-rays in 1895, many scientists began

to investigate their properties. When Marie needed a thesis topic in 1897,

it would have been natural to have looked in that area. Instead she chose

to work on the phenomenon of radioactivity, which had been discovered by

Becquerel the previous year and had attracted much less general attention.

So far uranium was the only radioactive element known; she set out to

discover whether there were others. Quite soon she found that thorium had

similar properties, unaware that the German physicist Erhard Schmidt had

made the same discovery and had already published it. However, in the

laboratory the Curies were encountering substances that were much more

strongly radioactive than thorium; one they called polonium was 350 times

as powerful. It was in their paper describing this discovery that the term

radioactive was used for the first time.

The Curies were working with a natural ore called pitchblende,

which consists mainly of uranium oxide. When they had removed all known

radioactive substances from this material there was still something else left,

and they decided to call it radium. They were determined to isolate it and

find out whether it was a new chemical element. In this quest another scientist,

named Gustave Bemont, was involved; the Curies acknowledged this

but just what he contributed is not clear. Others helped in different ways,

for example by lending them equipment. One of them remarked that it was

the amiable and self-deprecating Pierre who was the ingenious one, while

Marie provided the determination which kept the research going. She was

more the chemist, he the physicist. They soon concluded that, rather than

just the small quantities they had been using, they needed industrial quantities

of pitchblende. The chief European source of this expensive ore was

the St Joachimstal mine in Bohemia, then part of Austria-Hungary. The

Curies realized that, once the recoverable uranium had been extracted at

the mine, the massive first stage in their work would already have been

carried out. With the help of a scientist at the University of Vienna they

obtained samples, which confirmed that the unwanted residue contained

Marie Curie (1867–1934) 213

what they needed, and they discovered where it was being dumped. The

Austrian government was helpful and in due course a four-ton load of the

material arrived in sacks in the yard of the school of physics.

To refine this further they needed a much greater working space than

before. The best they could obtain was an abandoned shed once used by

the school of medicine as a dissecting room: ‘its glass roof did not afford

complete shelter from the rain; the heat was suffocating in summer, and

the bitter cold of winter was only a little lessened by the iron stove, except

in its immediate vicinity. We had to use the adjoining yard for those of our

chemical operations involving irritating gases; even then the gases often

filled our shed.’ However, the first stage involved heavy labour, as well as

irritating and even dangerous gases, while the later stages were extremely

delicate operations; the material they prepared was already showing visible

signs of radioactivity.

At the turn of the century Pierre and Marie had been married for

four years. Pierre’s father Eug`ene had moved to be near them and help

look after their daughter Ir `ene, now two years old. Not having attended

one of the Grandes Ecoles, Pierre was at a disadvantage when it came to

appointments; moreover, he was unduly modest about his very considerable

research achievements. After being passed over for the chairs of physical

chemistry and of mineralogy at the Sorbonne, he was offered an attractive

post at the University of Geneva, including a physics laboratory designed

to his own specifications, and an official position there for Marie. At first

they were tempted to accept. However, moving to Switzerland would have

seriously dislocated their research, setting it back by months, if not years,

at a time when they were becoming increasingly aware of competition to

isolate radium and establish that it was a new element. Some commercial

firms, with far greater facilities, were manufacturing radioactive material,

so that impure radium became readily available. This increased the chances

that someone else would beat the Curies to the object of their quest.

The question was resolved when a vacant chair was found at the

Sorbonne as a possible counter to the Swiss offer. The mathematician Henri

Poincar´e had been impressed by the Curies’ work and used his influence to

ensure that Pierre was appointed. At the same time Marie was offered a

part-time post teaching physics at an advanced ladies’ college in S`evres, so

they decided to remain in Paris. These appointments eased their financial

situation while committing them to additional teaching and other duties.

However, although others enjoyed better research facilities than they did,

no-one had greater determination. By March 28, 1902 they had refined just

214 From Ro¨ ntgen to Marie Curie

one tenth of a gram of radium chloride. Radium proved to be a million

times as radioactive as uranium; its atomic weight came out at 225.93. As

soon as the news spread around, the Curies found themselves famous, in

Britain even more than in France. There was great excitement when Pierre

lectured about their joint work at the Royal Institution and soon afterwards

the Royal Society awarded him the Davy medal.

After Marie had completed her doctoral thesis, the oral examination

was an emotional occasion. The crowd in the room where it was held

included family and friends, some girls from the school where she taught

and many supporters who burst into applause when, after she had disposed

of a few questions, the presiding examiner announced that she was now doctor

of physical science in the University of Paris and added the distinction

tr `es honorable. By chance Rutherford was in Paris at the time; he missed

the examination but met the Curies for the first time at the celebration

afterwards. As we shall see when we come to his profile, he resolved to provide

a definite theory of radioactive phenomena, something they had not

attempted to develop.

Unfortunately the Curies, who had been handling radioactive substances

for years, without any precautions, were now experiencing health

problems. Those around them were concerned at how ill they looked.

Pierre’s fingers were so painful that he could hardly write. Her hands were

painful also. She became pregnant again but the outcome was a miscarriage.

International recognition culminated in their being awarded the Nobel prize

for physics in 1903 for their joint researches on the radiation phenomena

discovered by Becquerel, with whom they shared the prize. Marie was the

first woman to become a Nobel laureate in the sciences and remained the

only one until her daughter Ir `ene was so honoured in 1935. The Curies gave

much of the prize money to good causes. Of course the floodgates of publicity

now swung wide open, much to their dismay. The lofty idealism of

her husband forbade him to court popularity, and the honours which now

were offered him were either declined or accepted with some reluctance. In

1905, after an earlier attempt had been unsuccessful, Pierre was elected to

the Paris Academy, at the age of forty-six. Ironically the state of his health

was such that he could no longer undertake experimental work. In the same

year Marie gave birth to their second daughter Eve (or Eva) Denise. Pierre

gave his Nobel lecture in Stockholm on their joint work.

A few months later, on a rainy April day, a heavy wagon drawn by two

carthorses was moving down the rue Dauphine near the Sorbonne when suddenly

a man holding an umbrella who was crossing the wet street appeared

Marie Curie (1867–1934) 215

to slip and fall under the wheels of the wagon. It was Pierre Curie, and he

was fatally injured. Marie was distraught when the news was broken to her.

Her sister Bronisl_awa came from Warsaw to comfort her. Later Marie published

his collected works, but first she was determined to complete the

research on which they had been engaged. Rutherford and others were not

convinced that polonium was an element, and there was even some doubt

in the case of radium. More dogged effort was required in order to settle

these questions. Rutherford wrote to his mother to tell her how ‘wan and

tired Marie looked and much older than her age. She works much too hard

for her health. Altogether she was a very pathetic figure.’ He sat next to her

at the opera one evening and could see that she was far from well; halfway

through the performance she left on his arm, completely worn out.

Within a month of the death of Pierre she was back in the laboratory,

having been made assistant professor, the first woman in France to reach

professorial rank. Within two years she had been appointed to the chair

at the Sorbonne her husband had held. On a site near the Sorbonne, the

Radium Institute was established, with one part devoted to pure research

into the chemistry and physics of radioactivity, under her direction, and the

other part to research on the application of radioactivity to the treatment

of disease. She moved with her two daughters to the Curie family home at

Sceaux, where the old doctor presided over the household and, assisted by a

succession of governesses from Poland, provided companionship for the girls

when their mother was out at work. The wealthy philanthropist Andrew

Carnegie met her and was deeply impressed, especially by her attitude as a

scientist on an equal footing with men. The result was the endowment of

the Curies Foundation, which was available to fund her research and provide

scholarships. She could now afford assistants in her scientific work. Several

of these were women, who developed a fierce loyalty to her.

For some years Marie Curie had taken her daughters for holidays to

a little place called l’Arcouest on the north coast of Brittany, sometimes

called Sorbonne-plage, because a small group of Paris academics, with their

families and friends, used to gather there regularly each summer. Eventually

it became like a second home for the Curie family. Ir `ene and Eve found

happiness there that was denied them in Paris, since their mother was not

so preoccupied with her work. Later on, however, the children were usually

sent to stay with relatives. In 1911, for example, they went to Poland

for the first time to stay with their Aunt Bronisl_awa. In 1913 they went

hiking in the Engadine in a party that included the Einsteins. According to

Einstein, Marie was like a herring, meaning that she had little capacity for

216 From Ro¨ ntgen to Marie Curie

either joy or pain and that the main way she expressed her feelings was by

grumbling.

Meanwhile Marie Curie was proposed for election to the Paris

Academy. The permanent secretary, Gaston Darboux, wrote to the press

explaining why he supported her candidature and specifying the practical

advantages membership of the academy would bring her. She might have

been the first woman to be elected to the Acad´emie des Sciences, although

one had just been elected to the literary Acad´emie Franc¸ aise. However, there

was a respectable rival candidate and, after a particularly close and tense

election, he was successful. Deeply hurt, Marie never allowed her name to

be put forward again. Much later she was elected to the Acad´emie de

M´edicine, another section of the Institut de France, due to the success of

radiotherapy in the treatment of tumours, although she was never directly

involved in the medical applications herself.

When she was widowed she was thirty-eight years old, strikingly

beautiful, some said it was the beauty of suffering. Her closest friends,

outside the family, were the physicists Paul Langevin and Jean Perrin, the

mathematician Emile Borel and their wives Henrietta Perrin and Marguerite

Borel. Old Dr Curie died early in 1910, after being bedridden for a year.

Following the death of her husband, Marie moved from central Paris to

the suburb of Fontenay-aux-Roses, where there was a colony of scientists,

including the Langevin family, who had moved there to get away from

the bustle of central Paris. Paul Langevin was one of those who played a

part in an educational cooperative that Marie organized, somewhat influenced

by the thought of Rousseau. In 1905 he had succeeded the deceased

Pierre Curie as professor at the Ecole de Physique et de Chimie. Four years

later he became director of studies at the school and was also made full

professor at the Coll`ege de France, having previously held junior positions

there.

Langevin had recently left his wife and taken an apartment in the

city, closer to the Ecole de Physique et de Chimie, where he frequently had

to work late at night. Marie Curie often visited him there. After having kept

to sombre clothing following her husband’s death, she now began to make

herself look attractive again. Her relationship with him was the only one

she was to have with a man who was not many years older than herself (in

fact Langevin was five years her junior). Besides offering much to enrich her

middle years, including a keen interest in politics, a love of literature and

music, and other common interests, he was able to provide an intellectual

bridge to the emerging new physics.

Marie Curie (1867–1934) 217

Marie Curie often naively misinterpreted what she believed to be

other people’s reactions to her actions. That she believed that she could

have a love affair with Langevin in which only a few friends and colleagues

would take any interest was a disastrous miscalculation. In the summer of

1910 at l’Arcouest, encouraged by the Perrins with whom she was sharing

a house, Marie started to urge Langevin to seek a divorce. Soon Langevin’s

wife was openly threatening to murder her.

She had been invited to attend the first of a series of small and

select conferences at which leading physicists met in Brussels to survey

and discuss, under luxurious conditions, the status of some important field

of physics. These were called Solvay conferences, after the wealthy Belgian

industrial chemist Ernest Solvay who sponsored them. Marie Curie arrived

in Brussels looking better in health, but very worried. The editor of a small

magazine called Le journal happened to be the brother-in-law of Langevin’s

wife. The headline ‘The Story of Love, Mme Curie and Professor Langevin’

appeared in the issue of Le journal of November 14, 1911; by the next day

every Parisian newspaper had the story and it was on its way to the tabloids

in other countries. Although the story that they had eloped was pure invention,

the affair rolled on day after day for the rest of the month. Back in

Paris she threatened to sue; there was a partial apology, but the damage to

her peace of mind was already severe.

Some letters Marie sent Langevin, locked up in his desk, had been

purloined and were now in the possession of his estranged wife, who was

seeking a legal separation. Adultery with Marie Curie was going to be alleged

when the Langevin separation case came to court. The suspense was broken

on November 23 when a magazine published long extracts from the

letters. Gustave T´ery, the journalist responsible, had been a contemporary

of Langevin’s at the Ecole Normale. He accused Langevin of being a cad and

a scoundrel. The existence of the letters could not be denied, but they had

been edited in such a way as to make them seem more sensational than

they really were. The relationship was of long standing; had Pierre Curie

been driven to suicide when he became aware of it?

Among her most loyal supporters at this difficult time were the

Borels. Emile Borel was at this time scientific director at the Ecole Normale

Sup´ erieure; it was his insouciante wife the writer Marguerite who was most

involved. When hostile crowds started to gather outside the Curie home in

Sceaux, she arrived to take Marie Curie and the children off to the Ecole

Normale Sup´ erieure, where the situation could be discussed within the

safety of the official apartment. The Minister of Public Instruction warned

218 From Ro¨ ntgen to Marie Curie

Borel that he should not be sheltering her in his official residence. Borel’s

father-in-law, Paul Appell, dean of the faculty of science, hitherto one of

Marie’s staunch supporters, was also furious that the Borels had become

involved; he and others thought that Marie should return to the land of her

birth, as did some members of her own family.

Libel actions were very expensive and unlikely to succeed; duelling

was both cheaper and quicker. At this late date duelling was a ritual performance,

seldom resulting in serious injury let alone death. Several duels

were fought over the Curie–Langevin affair, and Langevin himself decided

that he must challenge the journalist. Paul Painlev´ e, the future Prime

Minister, acted as one of his seconds. Langevin and T´ery confronted each

other with loaded pistols early on the morning of November 25, went

through the ritual and then withdrew.

Only a few days later, a telegram arrived from Stockholm, to say that

she had been awarded the Nobel prize in chemistry for the discovery of the

elements radium and polonium. She was the first person ever to be awarded

a Nobel prize in science twice, and this time the prize was not shared with

anyone else. However, the immediate effect was to revive the debate in the

press over the Curie–Langevin affair. There were those in the Sorbonne who

thought her culpable, as did many of the general public. A senior member of

the Nobel selection committee wrote to advise her not to come to Sweden to

accept the prize. Determined to receive the Nobel medal in her own hands,

she replied that she saw no connection between her scientific work and her

private life.

In fact the turmoil was beginning to subside. The separation case was

settled out of court without Marie Curie’s name being mentioned. However,

the strain of the elaborate Nobel ceremonies proved to be the last straw. On

her return to Paris she became gravely ill. She was also deeply depressed;

she later told her daughters that during this period she began to consider

suicide. When she had recovered she moved house and started to live under

her maiden name. Then she had a relapse and spent a month in an alpine

sanatorium. Her whereabouts were kept secret as far as possible.

Marie Curie was already in contact with leading members of the

suffragist movement in England, one of whom invited her over to stay.

She spoke English quite well and, travelling incognito, she had a blessed

relief from the unwelcome attention that pursued her in France. When she

returned to Paris she felt strong enough to pick up the threads of her life

again, although it was no longer possible that this could be shared with

Langevin. She started to use her married name once more, to the great relief

Marie Curie (1867–1934) 219

of her daughters. The new laboratory which had been promised her had just

been finished. For six months she was on sick leave, after medical treatment.

She left the house at Sceaux and moved into an apartment on the Ile St Louis.

Since her health was no better, she also spent time at various alpine spas.

Whether at this stage any or all of her suffering was due to radiation sickness

is not certain; there was also a suspicion of tuberculosis.

In 1914, when the First World War began, the French government

moved to Bordeaux for safety. Marie Curie took her precious store of radium,

a large portion of the world’s supply, to a bank there and then returned to

Paris. On the eastern front her native land, as so often before, was being

fought over by opposing armies. In the west the Germans had crossed the

Belgian border, and already casualties were mounting. Soon she received

a formal request from the Minister of War to equip operators for radiographic

work. She organized more than 200 mobile X-ray units and, with

her elder daughter, operated one herself. Most of her scientific friends were

also involved in war work.

With some reluctance she agreed to write her autobiography and to

visit America for the first time, to raise funds for her research. She took her

daughters with her. Rather as she had feared, she was lionized incessantly

and harassed by journalists, but thanks to American generosity her tour

was a huge success financially. Soon radium treatment was being given

at thousands of locations, although, among the medical staff concerned,

many were reporting sickness. Radiation affects healthy cells as well as

cancerous cells, but at first it was not realized how serious the consequences

could be. Marie Curie herself was particularly slow to recognize the dangers.

She suffered from cataracts, which can be an early symptom of radiation

sickness; she had them removed by surgery, but went to great lengths to keep

the operation secret. Those who met her for the first time were intimidated

by the glacial expression, caused by the treatment, in such contrast to her

gentle voice.

Despite her declining health, Marie Curie travelled widely, often in

the company of her younger daughter Eve. Ir `ene had been the favourite

daughter until her marriage, but now Eve began to take her place. Marie had

already built a holiday cottage in the north at l’Arcouest, for use in the summers,

which she put in the name of Ir `ene; now she built another at Cavalaire

on the Mediterranean, for use in the winters, which she put in Eve’s name.

Early in 1932 she had a fall and recovered from a fractured wrist unusually

slowly. At the end of the following year she was taken ill again, but made

a good recovery and, not without difficulty, continued to attend scientific

220 From Ro¨ ntgen to Marie Curie

conferences. She made a will and sent for her sister Bronisl_awa. She felt

exhausted; tuberculosis was diagnosed; the doctors again recommended an

alpine sanatorium. Once she was there the diagnosis was changed to pernicious

anaemia, then usually fatal. She died in her sixty-sixth year on July 4,

1934 and was buried next to Pierre, in the cemetery at Sceaux. The cause of

death was given as leukaemia, caused by prolonged exposure to high-energy

radiation. The first of many biographies, written by her younger daughter

Eve, was particularly influential in establishing her as a legendary figure,

but it does not tell the whole story. For example, the degree of financial

support she received in the early stages of her research is understated, and

the Curie–Langevin affair is glossed over.