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in 1822 of the critical state of liquids. For certain methods (notably the use of radioisotope labelling
liquids, when heated in a sealed tube, the meniscus and chromatography) became available. Photo-
disappears and liquid and vapour become indistin- synthesis is the process whereby green plants
guishable at a critical temperature. Cagniard was absorb carbon dioxide from the air and convert it
also an inventor; his best-known device being the by complex stages into starch and into oxygen
disk siren (in which a note is produced by blowing (which is discharged into the air, at the rate of
about 1012 kg per year). This can be claimed as the
air through holes cut in a spinning disk).
Cailletet, Louis Paul [kiytay] (1832–1913) French most important of all biochemical processes, since
physicist: pioneer of liquefaction of gases. animal life also depends on plant foods and on the
Cailletet studied in Paris and then returned to oxygen-rich atmosphere which, over geological
Chatillon-sur-Seine to manage his father’s ironworks. time, photosynthesis has provided.
His first interest was metallurgy, which led him to Calvin allowed the single-celled green algae
study blast furnace gas and to interest himself in gas Chlorella to absorb radioactive CO2 for seconds only,
properties. At that time, attempts to liquefy some and then detected the early products of reaction. By
gases (for example H2, N2 and O2) had all failed and 1960 he had identified a cycle of reactions (the
they were classed as ‘permanent gases’. Cailletet reductive pentose phosphate or Calvin cycle) which
learned of T Andrews’s work on critical tempera- form an important part of photosynthesis. He was
ture, which suggested to him that more cooling was awarded the Nobel Prize for chemistry in 1961.
Camerarius, Rudolf Jakob [kamerayreeus] (1665–
needed, as well as pressure, for success. He used the
Joule–Thomson effect (the cooling which occurs 1721) German botanist: demonstrated sexual
when a gas expands through a nozzle), followed by reproduction in plants.
pressure, and by 1878 had liquefied these ‘perma- Camerarius followed his father as professor of
nent’ gases. He was interested in flying (even in medicine at Tübingen, and he was also director of
advance of the development of the aeroplane) and the botanic garden there. Ray and others had sug-
the sundry devices he invented included a high-alti- gested that plants can reproduce sexually, but it
tude breathing apparatus and an aircraft altimeter. was Camerarius who first showed by experiment
Calvin, Melvin (1911–97) US biochemist: elucidated that this is so. In 1694 he separated some dioecious
biosynthetic paths in photosynthesis. plants (ie plants in which the male and female flow-
Calvin studied at Michigan, Minnesota and ers are borne on separate plants) and showed that
Manchester and then began teaching at the although the pistillate plants gave fruit, they did
not produce seed in the absence of staminate flow-
ers. He identified the stamens as the male plant
organs and the carpels (consisting of the style,
ovary and stigma) as the female apparatus of a
flowering plant. He also described pollination.
Candolle, Augustin-Pyramus de [kãdol] (1778–
1841) Swiss botanist.
Candolle studied in Geneva and Paris, and from
1806–12 made a botanical survey of France as a gov-
ernment commission. His ideas on taxonomy, set
out in his Elementary Theory of Botany (1813), devel-
oped from and replaced the schemes due to Cuvier
and Linnaeus and were used for 50 years. He
believed that morphology, rather than physiology,
should be the basis of taxonomy and that relation-
ships between plants could be best seen by studying
the symmetry of their sexual parts. From this he
was led to the idea of homology. He also studied
plant geography and the influence of soil type in
his travels to Brazil and the Far East. He taught at
Montpelier and, from 1816, at Geneva.
Melvin Calvin in 1961.
59
Cannizzaro, Stanislao

Cannizzaro, Stanislao [kaneedzahroh] (1826– College in 1884. For the next 10 years she lived at
1910) Italian chemist: resolved confusions on home but after the death of her mother she
atomic and molecular mass. returned to study physics at Wellesley, and special-
Cannizzaro began his university life as a medical ized in astronomy at Radcliffe College. In 1896 she
student, but attended a variety of courses and was appointed by E C Pickering (1846–1919) to the
became attracted to chemistry, partly because he staff at Harvard College Observatory where she
saw it as the basis of physiology. In 1847 he joined began the study of variable stars and stellar spectra.
the rebel artillery in one of the frequent rebellions These spectra were studied by Pickering’s objective
in his native Sicily, where his magistrate father was prism method, which made spectra visible even
at the time chief of police. The rebellion failed, and from faint (9th or 10th magnitude) stars. Colour
Cannizzaro wisely continued his chemistry in film was not available and classification by eye was
Paris, with Chevreul. He returned to Italy 2 years a skilled task.
later, teaching chemistry in three universities, all Her first major publication (1901) was a catalogue
poorly equipped. In 1853 he discovered the Canniz- of 1122 southern stars which built upon the early
zaro reaction, in which an aldehyde (aromatic, or classification used by Williamina Fleming (1857–
having no alpha-hydrogen) is treated with a strong 1911). Annie Cannon’s system represented a
base to give an acid and an alcohol: sequence of continuous change from the very hot
2 RCHO + NaOH → RCO2Na + RCH2OH white and blue stars of types O and B, which showed
However, his main work was done in 1858, when many helium lines, through the less hot stars of
he cleared the way to a single system of relative types A, F, G and K to the very red stars of type M,
atomic and molecular mass. He did this by seeing which were cool enough that compounds of chemi-
the value of the theory due to Avogadro (then cal elements, such as titanium and carbon oxides,
dead) and using it to deduce that common gaseous could exist in their atmospheres. However, it was
elements existed as molecules (H2, N2, O2) rather not then known that it was a temperature sequence.
than as single atoms. With this in mind, Avogadro’s In 1910 Annie Cannon’s scheme was adopted as the
Law enables relative atomic and molecular mass to official classification system at all observatories.
be deduced from the densities of gases and vapours. Her most important work was the Henry Draper
(Initially, as hydrogen gas was the lightest known, Catalogue of Stellar Spectra, published by the Harvard
the hydrogen atom was assigned atomic mass Observatory between 1918 and 1924, which lists
= 1; we now use as a basis the common isotope of the spectral types and magnitudes of 225 300 stars,
carbon = 12, which gives a very similar scale.) all those brighter than ninth magnitude, giving
Cannizzaro’s fervour as a speaker at a chemical con- their positions and visual and photographic mag-
ference in 1860, and a pamphlet he distributed nitude. In 1922 the classification system used by
there, convinced most chemists and removed basic her in the catalogue was adopted by the
ambiguities in chemical ideas during the 1860s. International Astronomical Union as the official
The half-century of confusion on atomic mass system for the classification for stellar spectra. She
which had followed Dalton’s atomic theory had then began on an extension to fainter stars, in
ended. selected regions of the sky, down to about the 11th
He became a Senator in 1871 and afterwards magnitude, and was occupied with this task until
worked mainly on public health. her death. She discovered 277 variable stars and
Cannon, Annie Jump (1863–1941) US astronomer: five novae.
compiled Henry Draper catalogue of variable stars. Annie Cannon received many academic honours;
Originally interested in astronomy by her she received honorary degrees from four universi-
mother, Annie Cannon graduated from Wellesley ties, including Oxford, where she was the first
woman to be honoured with a doctor’s degree
(1925). (See panel opposite.)
Cannon, Walter Bradford (1871–1945) US physi-
ologist: introduced first radio-opaque agent.
Cannon was very much a Harvard man; he was an
arts student there, then a medical student, and pro-
fessor of physiology from 1906–42. Röntgen dis-
covered X-rays in 1896 and the next year Cannon,
still a student, tried feeding a cat a meal containing
a bismuth compound to give an X-ray ‘shadow’ of
its alimentary tract. The method worked, and made
the mechanics of digestion visible; and, with a
barium compound in place of bismuth, it has been
used in diagnostic radiography ever since. Cannon
went on to work on the effect of shock and emotion
on the nervous system and the transmission of
nerve impulses. He developed Bernard’s concept of
the importance of a constant internal physiological
environment (ie a narrow range of salt, sugar,
Annie Cannon
60
Panel: The entry of women into astronomy


THE ENTRY OF WOMEN Unlike other sciences, astronomy caught the interest
INTO ASTRONOMY of the population with its giant telescopes, its new
visible discoveries and royal connections. Caroline
The early route to professional astronomy for men in Herschel was granted a pension of ÂŁ50 a year by King
Britain was by a degree in mathematics or mathemat- George III and the Gold Medal for Science by the king
ical physics, then through paid work as an assistant of Prussia.
at a major observatory. For women this path was not MARIA MITCHELL in the USA learned mathematics
available, as positions in observatories were not and astronomy initially through her father and used
open to them and the opening of women’s colleges his instruments. In 1847 she won the Gold Medal
did not at first enable them to become professional offered by the king of Denmark for the discovery of a
astronomers. The opening of Queen’s College (1848) new comet, which led to her further astronomical
and Bedford College (1849), London, provided tuition career. She became professor of astronomy and
in mathematics and physics for women but unless director of the observatory at Vassar College, New
they had access to instruments owned by their rela- York.
tives, practical observation was not possible. MARY BLAGG became interested in the subject
In the USA, Vassar, Smith, Mt Holyoke and other through University Extension lectures, worked in
women’s colleges had departments of astronomy and lunar nomenclature and was admitted as one of the
employed women to teach and run their observato- first female Fellows of the RAS in 1916. Margaret
ries. Positions in computing, though poorly paid, Lindsay Murray (1849–1915) was interested in
allowed women in the USA to enter into astronomical astronomy from childhood and built a small spectro-
work, while in Britain such work was done by young scope. After she married WILLIAM HUGGINS she
men. worked as his assistant for 30 years, and papers were
For women interested in astronomy in Britain a published in their joint names. Mary Acworth Orr
scientific society was the main focus of activity. After (1867–1949) joined the recently formed British
1838 women were permitted to attend the mathe- Astronomical Association in 1895. She observed vari-
matics and physics section of the British Association able stars and the solar eclipses of 1896 and 1900.
for the Advancement of Science. The Royal She married astronomer John Evershed and went
Astronomical Society admitted women as honorary with him to Kodaikanal Observatory in India to work
Fellows (to attend lectures) from 1835 and as ordi- on the distribution and motion of solar prominences.
nary Fellows (full members) in 1916. In the USA, Williamina Fleming (1857–1911) was
In the 17th-c and 18th-c a number of women in working as a maid in the household of Edward
Germany and France had made contributions to Pickering (1846–1919), director of the Harvard
astronomy by assisting their families and friends in College Observatory, when she was offered part-time
observations, calculations and catalogues of stars. work at the Observatory in computing. She
NICOLE-REINE ETABLE DE LABRI-LEPAUTE in France had became a permanent member of the staff in 1881
assisted A-C Clairaut (1713–65) to determine the and took charge of the classification of stars on the
exact time of the return of HALLEY’S comet. basis of their photographed spectra, developing a
CAROLINE HERSCHEL assisted and was trained by her useful classification scheme, published as the Draper
brother. In 1835 she was one of the first two women Catalogue of Stellar Spectra in 1890. This work was
elected to honorary Fellowship of the RAS; the other the result of a fund established by the widow of
was MARY SOMERVILLE, who explained the latest astro- Henry Draper (a Harvard College physician and
nomical discoveries in her books popularizing science eminent amateur astronomer) as a memorial to her
and so made the subject more accessible to women. husband. ANTONIA MAURY, the niece of Henry Draper,


oxygen and temperature in the living body) which cine. He was unable to enter the college of physi-
he named homeostasis, and he studied the mecha- cians because of his birth, but eventually gained
nism which achieves this essential equilibrium. recognition through his work and became profes-
Later he applied similar ideas to political and social sor of medicine at Pavia in 1544 and at Bologna in
organizations, but without the same success. 1562. His work in medicine is now eclipsed by his
Cardan, Jerome, Girolamo Cardano (Ital), distinction as one of the greatest algebraists of his
Hieronymus Cardanus (Lat) (1501–76) Italian math- century. He recognized negative and complex roots
ematician and physician: gave general algebraic for equations, found the relations between the
method for solving cubic equations. roots of an equation and the coefficients of its
Cardan was the illegitimate son of a Milanese terms, and gave a general algebraic method for
lawyer, a situation which caused difficulty for him solving cubic equations (Cardan’s solution). He has
both practically and emotionally. He was taught been accused of pilfering parts of this method from
mathematics by his father when young and edu- Tartaglia, but the accusation has been contested.
cated at Pavia and Padua where he studied medi- His contribution to chemical thought is more
61
Carlson, Chester


graduated from Vassar College in 1887 and worked its luminosity and that, based on this, their distances
at the Harvard Observatory classifying the bright could be calculated. Previous to her discovery only
northern stars according to their spectra. ANNIE JUMP the distance of relatively nearby stars (up to 100 light
CANNON graduated from Wellesley College in 1884 years away) could be found, by measurement of
and joined the team of women, appointed by stellar parallax.
Pickering, working on variable stars and stellar During the first 30 years of the 20th-c the number
spectra. She built upon the previous classification of women working as paid computors increased
schemes to publish her own, and in 1922 her system rapidly; many of them had no university education
was adopted by the International Astronomical and they rarely made a career of their ill-paid work.
Union as the official system for the classification of Most women graduating in mathematics and physics
stellar spectra. As Agnes Mary Clerke (1842–1907), a in Britain went into teaching. Six women gained a
writer on popular astronomy, foresaw in 1902, work PhD during this time. Dorothy Wrinch (1894–1976)
in this area was to lead later to modern theories of researched at Oxford and Cambridge, became an X-
stellar evolution. ray crystallographer and emigrated to the USA.
Fiammetta Wilson (1864–1920) joined the British Bertha Swirles gained a PhD at Cambridge in 1929
Astronomical Association and began observing and published on mathematical physics and theoreti-
planets, comets and meteors; she observed over cal astrophysics. She became director of studies in
10 000 meteors between 1910 and 1920, was mathematics at Girton College, Cambridge and
appointed joint acting head of the meteor section married the astronomer and geophysicist HAROLD
during the First World War and was admitted to the JEFFREYS. CECILIA PAYNE-GAPOSCHKIN studied physics
RAS in 1916. DOROTHEA KLUMPKE, an American who and astronomy at Cambridge, joined the BAA and
was educated in Europe, was the first woman to was elected to the RAS. Her postgraduate research at
gain a PhD in maths at the Sorbonne. She joined the Harvard College Observatory in the USA, on the ele-
staff at the Paris Observatory, became the first ments present in stellar atmospheres, was described
woman to make astronomical observations from a by Otto Struve (1897–1963) in 1962 as ‘undoubtedly
balloon and remained in France throughout her the most brilliant PhD thesis ever written in astron-
working life. omy’, presumably of those he had seen. After a brief
Agnes Mary Clerke followed Mary Somerville into return to Britain where she gave a paper to the 1925
popular science writing, contributing to the meeting of the BAA , she returned to the USA and a
Dictionary of National Biography from 1885–1901 distinguished career at Harvard. Openings for a
and to the ninth edition of the Encyclopaedia career in astronomy in Britain were then still hard to
Britannica. A Popular History of Astronomy during find.
the 19th Century (1885) by her was valuable for its In the later 20th-c, several women have achieved
discussion of the introduction and application of the distinction and careers in astronomy in Britain. Best
spectroscope, remained in print for 23 years, and had known are JOCELYN BELL BURNELL, co-discoverer of the
a German translation. She was elected an honorary first pulsar, MARGARET BURBIDGE, who made major
Fellow of the RAS in 1903 and has a lunar crater contributions to ideas on quasars, on the synthesis of
named for her. the nuclei of atoms in the stars and on the masses of
HENRIETTA LEAVITT graduated at Radcliffe and galaxies; and Heather Couper, prolific writer on
joined the Harvard Observatory in 1895. Studying astronomy.
stellar brightness by photographic methods, she
deduced that Cepheid variable stars have a simple
MM
relationship between the period of a given star and


substantial than is often recognized. He wrote an talents emerged and were acknowledged late in
encyclopedia of the sciences which discusses the life. His eldest son was convicted and beheaded for
major chemical theories of the time. He was credu- wife-murder and his second son was exiled at
lous in many ways, but critical of alchemical Cardan’s instigation as ‘a youth of evil habits’.
claims. He recognized only three Aristotelian ele- Cardan describes himself in his autobiography as
ments (earth, water and air), arguing ahead of his ‘timid of spirit, I am cold of heart, warm of brain
time that fire is not a substance but a form of and given to never-ending meditation. I ponder
motion; and he distinguished between electrical over ideas ...’. He was a man who made more ene-
and magnetic attraction. His writing includes a mies than friends.
Carlson, Chester (1906–68) US physicist: inventor
variety of chemical recipes and his chemical and
clinical interests are brought together in a text on of xerography.
toxicology. Carlson worked for a printer before studying
Cardan’s life was not easy: his childhood was physics at the California Institute of Technology; he
marred by ill-health and harsh treatment while his then worked for the Bell Telephone Company
62
Carnot, Sadi

before taking a law degree and moving to the increase in the amount of neurotransmitter at
patent department of an electronics firm. During some synapses. In contrast to this short-term
the Depression he decided that invention was a way memory, a strong stimulus whose effect is retained
to prosperity and in his spare time he searched for for weeks is linked with increased protein forma-
a cheap, dry method of copying documents. After tion at the synapse. If this protein formation is pre-
three years he focused on a scheme using electro- vented, long-term memory is blocked but not
static attraction to cause powder to adhere to plain short-term memory. In the 1990s Kandel showed
paper, and got his first copies in 1938. It took that similar changes could be found in mice, and
another 12 years and a team of co-workers to fairly certainly apply to humans.
Carnot, (Nicolas LĂ©onard) Sadi [kah(r)noh]
develop a commercial xerographic copier; he died a
very wealthy man. (1796–1832) French theoretical physicist: a founder
Carlsson, Arvid (1923– ) Swedish pharmacologist: of thermodynamics through his theoretical study
his work led to knowledge of Parkinson’s disease of an idealized heat engine.
and of schizophrenia at the cellular level, and to Carnot’s family was unusual. His father, Lasare
new drugs to treat them. Carnot (1753–1823), was the ‘Organizer of Victory’
Carlsson qualified in medicine at Lund in 1951, for the Revolutionary Army in 1794 and became
and worked thereafter in pharmacology at Napoleon’s minister of war; unusually, he left poli-
Gothenburg in Sweden, studying especially the tics for science in 1807 and did good work in pure
action of drugs on the brain. Before his work it was and applied mathematics and in engineering. Sadi
known that the human brain contains about 1011 had one brother, Hippolyte, also a politician, whose
nerve cells (neurons) each with complex connec- son became president of France. Sadi was educated
tions; their tree-like shape allows each neuron to by his father and at the École Polytechnique, and
connect with thousands of neighbours. These con- served in the army as an engineer, leaving it as a
nections or contact points (synapses) allow electri- captain in 1828. He was a cholera victim in the Paris
cal signals to be passed between neurons, through epidemic of 1832.
a chemical transmitter at the synapse. In the 1950s His scientific work was highly original, and the
Carlsson examined the action of the plant alkaloid single paper he published before his early death did
reserpine on brain cells in rabbits: at that time it much to create the new science of thermodynam-
was used to treat schizophrenia. He found that ics. His paper was Reflections on the Motive Power of Fire
reserpine reduced the amount of a rather simple (1824) and it originated in Carnot’s interest in
brain chemical, dopamine, in one type of neuron. steam engines, which had been developed by
Given a sufficient dose of reserpine, the rabbits British engineers and, as the nationalistic Carnot
became immobile, and Carlsson noted that they realized, were generating an industrial revolution
showed similarities to human patients with severe in the UK. However, their theory was non-existent
Parkinson’s disease. He found that the ‘frozen’ rab- and their efficiency very low. Carnot set out to
bits recovered if they were given the synthetic deduce if the efficiency could be improved and
chemical levodopa, which compensated for their whether steam was the best ‘working substance’.
depleted dopamine. Since this work levodopa has His paper is a brilliant success, despite the fact that
been widely used to treat parkinsonism. From
Carlsson’s work it seems that the level of the neu-
rotransmitter dopamine in the brain is critical: a
deficit leads to the loss of movement control char-
acteristic of parkinsonism, but an excess of
dopamine produces the psychotic state of schizo-
phrenia, and drugs useful in treatment of the latter
disease are dopamine-inhibitors.
Carlsson later worked on antidepressive drugs,
developing the selective serotonin re-uptake block-
ers, which have largely replaced earlier antidepres-
sants. He was awarded the Nobel Prize for
physiology or medicine in 2000, sharing it with
Paul Greengard (1925– ) of Rockefeller University,
New York, who from the 1960s studied in detail the
way in which dopamine initiates a series of changes
in neurons. The third sharer of the prize, Eric
Kandel (1929– ) of Columbia University in New
York also worked in neuroscience. His studies on
memory used the sea slug Aplysia. This has few
nerve cells (20 000), many of them large. It does not
remember much; but if its protective gill reflex is
strengthened by a stimulus, this amplified reflex is
retained for days or weeks. Kandel showed that a Sadi Carnot, in his uniform as a trainee army engineer at
weak stimulus, retained only for hours, is due to the École Polytechnique.
63
Carothers, Wallace Hume

he used the caloric theory of heat, which presumed York. He remained there until retirement in 1939,
it to be a ‘subtle fluid’. (This did not affect the main except for an interlude as a French Army surgeon in
answers and, incidentally, Carnot’s notes show the First World War (when he shared the introduc-
that long before his death he was converted to tion of the Carrel–Dakin solution (mainly NaOCl)
modern heat theory.) He also used the correct idea for the antiseptic treatment of deep wounds). Even
that perpetual motion is impossible, a fact of before the First World War he began to attack the
experience. problem of organ transplantation. One difficulty in
In his paper, Carnot considers an idealized steam this is the need to ensure a blood supply to the
engine, frictionless, with its working substance transplanted organ without failure due to throm-
passing from heat source to heat sink through a bosis or stenosis. Carrel developed methods for
series of equilibrium states, so that it is truly suturing blood vessels with minimum damage and
reversible. The pressure–volume changes in it con- risk of infection or thrombosis. These techniques
stitute a Carnot cycle. He was able to show that the greatly advanced vascular surgery. He even sug-
efficiency of such an engine depends only on the gested, in 1910, the coronary bypass procedure and
temperature (T1) of the heat source and the tem- carried it out on a cadaver. The method was not
perature (T2) of the heat sink; that the maximum usable on living patients until half a century later.
fraction of the heat energy convertible into work is He won an unshared Nobel Prize in 1912.
(T1 – T2) /T2; and that it does not depend at all on the He went on to study methods of keeping organs
working substance (Carnot’s theorem). These ideas, alive by perfusion (ie passage of blood or a blood
which were eventually to mean so much for both substitute through the organ’s blood vessels). With
engineers and theoreticians, were too abstract to C Lindbergh (1902–74), the aviator, he produced a
attract much interest in 1824. In 1849 when W perfusion pump (‘artificial heart’) in 1935. Major
Thomson saw the paper he realized its importance, advances (eg in dealing with rejection of donor tis-
and he and Clausius made it widely known. sues) were needed before transplants of organs
The paper contains ideas linked with the laws such as the kidney could be achieved by others after
of conservation of energy and the First Law of the Second World War, but Carrel’s methods were
Thermodynamics, and led Thomson and Clausius essential for that later success.
Carrington, Richard Christopher (1826–75) British
towards the Second Law. Later still, Gibbs and
others were to use thermodynamic ideas to forecast astronomer: discovered differential rotation of Sun
whether chemical reactions will occur. with latitude.
Carothers, Wallace Hume [karutherz] (1896– A wealthy amateur, Carrington made over 5000
1937) US industrial chemist: discovered fibre-form- observations of sunspots between 1853 and 1861,
ing polyamides (nylons). and showed that the Sun does not rotate as a solid
The son of a teacher, Carothers graduated from a body but that its rotational period varies from 25
small college and later both studied and taught days at the equator to 27.5 days at latitude 45°. He
chemistry at three universities before moving in also discovered solar flares in 1859.
Carson, Rachel Louise (1907–64) US naturalist and
1928 to the research department of the Du Pont
Company at Wilmington, DE. His object was ‘to syn- science writer: warned of the dangers of modern
thesize compounds of high molecular mass and synthetic pesticides.
known constitution’; an early success was Rachel Carson was born in Springdale, PA, and
Neoprene, the first successful synthetic rubber, studied biology at Johns Hopkins University. After
marketed from 1932. He then studied the linear teaching at Maryland (1931–36) she worked as a
polymers made by condensing a dibasic acid with a marine biologist for the US Fish and Wildlife
diamine. By heating adipic acid with hexamethyl- Service (1936–49). In The Sea Around Us (1951) she
enediamine at 270° he obtained Nylon 6.6, which warned of the increasing danger of large-scale
can be melt-spun into fibres whose strength is marine pollution. With The Silent Spring (1962),
improved by cold-drawing: however, she created an awareness world-wide of
HO2C(CH2)4CO2H + H2N(CH2)6NH2→ the dangers of environmental pollution and roused
...CONH(CH2)6NHCO(CH2)4... public concern for the problems caused by modern
This polyamide has a relative molecular mass of synthetic pesticides and their effects on food
10–15 × 103, with useful properties as a textile fibre, chains. Her work was the starting point for the
and has had much commercial success. Carothers increasing ecological and conservationist atti-
established useful principles in research on poly- tudes emerging in the 1970s and 1980s. Although
mers. He had a history of alcoholism and depres- generally desirable these new ‘green’ attitudes can
sion, and soon after his marriage he killed himself. be unfortunate: eg in Sri Lanka there were 2.8 mil-
Carrel, Alexis (1873–1944) French–US surgeon: pio- lion cases of malaria in 1948 but by 1963 this had
neer of vascular surgery and perfusion methods. been cut to 17 cases by DDT spraying. As a direct
Carrel qualified in medicine at Lyons in 1900. He result of Carson’s The Silent Spring spraying was
was a skilful surgeon, but lacked interest in routine stopped in 1964 and by 1969 there were 2.5 million
surgery and in 1904 visited Canada, intending to cases. Much study of DDT, introduced by P H
become a cattle rancher. However, later in 1904 he MĂĽller, has shown it can damage food chains for
moved to Chicago and in 1906 joined the some birds and fishes and accumulates in the
Rockefeller Institute for Medical Research in New human liver.
64
Cavalli-Sforza, Luigi Luca

Casimir, Hendrik (Brugt Gerhard) (1909–2000) The Terror of 1793–4 drove the Cauchy family to
Dutch physicist: originated the ‘two-fluid’ model of their country retreat at Arcueil, and there Augustin
superconductivity. was educated by his father. He also became badly
Casimir was educated at the universities of malnourished, which affected his health for the
Leiden, Copenhagen and Zürich. He held a variety rest of his life. In 1805 he entered the École
of research positions until, in 1942, he began a Polytechnique, and after moving to the École des
career with Philips. He became director of the Ponts et Chaussées served as an engineer in
Philips Research Laboratories in 1946. Napoleon’s army. In 1813 ill health caused his
Casimir’s papers cover aspects of theoretical return to Paris; 3 years later he became a professor
physics, particularly low-temperature physics and at the École Polytechnique. With the restoration of
superconductivity. W Meissner (1922– ) had the Bourbons and departure of republicans such as
examined some properties of superconductors, Monge and others, Cauchy was elected to the
such as the expulsion of a magnetic field below the Académie des Sciences, which, in the same year
superconducting transition temperature (the (1816), awarded him its Grand Prix for his paper on
Meissner effect). Casimir and C Gorter proposed in wave modulation. His recognition and status
1934 that two sorts of electrons exist, normal and increased (including a chair at the Collège de
superconducting, and used this to explain the rela- France), but all was lost with Charles X’s abdication
tion between thermal and magnetic properties in in 1830, following the July Revolution. Cauchy was
superconductors. When Bardeen and others pro- extremely pious and, although sincere, was ‘a big-
duced the BCS theory it was clear that the two cate- oted Catholic’ even according to Abel. He refused to
gories represented unpaired electrons and paired take a new oath of allegiance and went into exile.
electrons (called Cooper pairs). A professorship at Turin followed, together with
Casimir in 1948 predicted the effect named for a tedious period as tutor to Charles X’s son in
him: an attractive force that occurs between two Prague. Although Cauchy stuck to his principles,
parallel conducting plates when they are about the Government fortunately turned a blind eye and
10–5 m apart. It was verified experimentally in in 1838 he returned to a professorship at the École
1958. Polytechnique, and at the Sorbonne in 1848. He
Cassini, Giovanni Domenico [kaseenee] (1625– died of a fever at the age of 68, after a highly
1712) Italian–French astronomer: greatly enhanced creative lifetime in mathematics, and mathematical
knowledge of the planets. physics, which included seven books and over 700
Born in Italy, Cassini became director of the Paris papers. His tally of 16 named concepts and theorems
Observatory in 1669 and never returned to Italy. He compare with those of any other mathematician.
added greatly to our knowledge of the planets of Cauchy played a large part in founding modern
the solar system. It was he who worked out the rota- mathematics by his introduction of rigour into cal-
tional periods of Jupiter, Mars and Venus and tabu- culus and mathematical analysis. He published on
lated the movement of the Jovian satellites convergence, limits and continuity and defined the
discovered by Galileo (Römer subsequently used integral as the limit of a sum. Together with Gauss,
his results to calculate the speed of light). Between Cauchy created the theory of real and complex
1671 and 1674 he discovered four new satellites of functions, including complex analysis and contour
Saturn (Iapetus, Rhea, Dione and Tethys) and in integration. He recognized the theory of deter-
1675 observed the gap in Saturn’s ring system first minants and initiated group theory by studying
noted 10 years before by William Balle and now substitution groups.
Cavalli-Sforza, Luigi Luca (1922– ) Italian
known as the Cassini division. Most importantly,
he was able to calculate the first reasonably accu- geneticist: leading figure in the development of
rate figure (only 7% low) for the Earth’s distance population genetics.
from the Sun (the astronomical unit). To do this Cavalli-Sforza graduated in medicine at Pavia in
he observed Mars from Paris at the same time as 1944, and afterwards worked in bacterial genetics
Jean Richer (1630–96) observed it from Cayenne in Cambridge, Milan, Parma and Pavia before he
in French Guiana, 10 000 km away. (Jupiter’s satel- became professor of genetics at Stanford, CA, from
lites provide a universal clock; when they are 1970–92. Population genetics is concerned with the
seen in the same positions at both sites, the time is links between human genes and the location and
the same.) The parallax gave the distance of Mars, movement of races or peoples: it can use both living
and Kepler’s Third Law then gave the distances of and long-dead material for DNA studies of genes,
the other planets. In later life he attempted to and its results can be correlated with language and
measure the shape of the Earth but concluded cultural characteristics. Thus the Basque people,
incorrectly that it was a prolate spheroid. Three mainly found in northern Spain, have a high inci-
generations of his descendants succeeded him as dence of a gene linked with the Rhesus-negative
director of the Paris Observatory; all were highly blood group: they also share a distinctive language,
conservative astronomers, resisting major new one of the very few non-Indo-European languages
theories. in Europe. Cavalli-Sforza showed that to under-
Cauchy, Augustin Louis, baron [kohshee] (1789– stand human evolution, ‘genetic drift’ (the Sewell
1857) French mathematician: founded complex Wright effect) as well as natural selection is impor-
analysis. tant: for this he used the Church’s 300-year archive
65
Cavendish, Henry

of births, marriages and deaths for 100 Italian vil- Cambridge, took no degree and studied in Paris for
lages, and linked this with his sampling of blood a year before making his homes in London (for
from present villagers to find the frequency of living, Gower Street; workshop and laboratory,
A,B,O blood groups. Others have since worked on Clapham; library, Dean Street, Soho). Thereafter he
genes found in mitochondrial DNA, which is devoted his time and money to personal research in
passed only in the female line, and changes only by chemistry and physics. He had a most peculiar per-
mutation, at a rate of 2–4% per million years. Work sonality: although he enjoyed scientific friends and
on these lines has made firm the view that modern discussion, he otherwise avoided conversation to
Homo sapiens are all descended from one group an extreme degree, especially with women. He was
which evolved in Africa a few hundred thousand generous with money, but not to himself. He pub-
years ago. lished only a part of his scientific work, although
Studies on New World populations using DNA, he was unperturbed by either jealousy or criticism.
linguistic and dental evidence all point to three When he was 40 he inherited a large fortune, but he
waves of migration from Siberia over 10 000 years was not interested in it, although he did use part of
ago, into North America when it was then linked by it to form a library and apparatus collection. This
land (Beringia). At about the same time the earliest was used by the public and by himself on the same
neolithic farmers expanded from the Middle East terms, and characteristically was located well away
into Mediterranean Europe, reaching France, from his house. He was described as ‘the richest of
Britain and Scandinavia about 6000 years ago: the learned and the most learned of the rich’ and as
thereafter both mixing with and overwhelming the having ‘uttered fewer words in the course of his life
native hunter–gatherers, who had different fre- than any man who lived to fourscore years’.
quencies for the 95 genes studied. Cavalli-Sforza’s In 1766 he described methods for handling and
classic History and Geography of Human Genes (1994) weighing gases. He studied ‘fixed air’ (CO2), show-
surveys migrations in all continents; his conclu- ing that it was produced by fermentation or from
sions are not universally accepted, as is inevitable acid and marble, and he re-studied ‘inflammable
in a developing science with much to offer archae- air’ (H2, which had been studied by Boyle). He
ology and anthropology. exploded mixtures of hydrogen and air with an
Cavendish, Henry (1731–1810) British chemist and electric spark, and found that no weight was lost and
physicist: studied chemistry of gases and of air, that the product ‘seemed pure water’ (1784). The
water, and nitric acid; made discoveries in heat and volume ratio he found to be 2:1; and the synthesis of
electricity and measured the density of the Earth. water in this way cast out the long-held idea that
As eldest son of Lord Charles Cavendish, Fellow of water was an element. These experiments also con-
the Royal Society, and grandson of the 2nd Duke of vinced Cavendish that heat was weightless. He exam-
Devonshire, Henry was wealthy and well-educated. ined air from different places, heights and climates,
His mother died when he was 2. He spent 4 years at and showed it to be of nearly constant composition.
He showed that nitric acid is formed by passing
sparks through air (when N2 and O2 combine and the
NO reacts with water). Cavendish, like Priestley,
interpreted his results on the phlogiston theory and
Cavendish thought hydrogen was phlogiston.
Cavendish, unlike Priestley, realized that Lavoisier’s
theory would also explain his results. He noticed that
a small residue (1%) of air remained after long spark-
ing; this was later found by Ramsay and Rayleigh to
be argon, a noble gas and a new element.
In physics, Cavendish used a method devised by
Michell to determine the gravitational constant
(G) in 1798. Bouguer had earlier attempted to find
the density of the Earth; Cavendish’s value for G
(from which the Earth’s mass and density is easily
calculated) gave a mean density of nearly 5.5 times
that of water. (Boys obtained a slightly more accu-
rate value, by the same method, a century later.)
Since most rock has a density in the range 3–4, a
metal core for the Earth could be deduced. Most of
Cavendish’s work on heat and electricity was not
published by him, but was revealed from his notes
after 1879 by Maxwell. He showed that Cavendish
had distinguished between quantity and intensity
of electricity and that he had measured the electri-
Henry Cavendish: the only portrait, claimed to have been
cal conductivity of salt solutions. He had proved
made without his knowledge by W Alexander.
that the inverse square law (Coulomb’s law) holds
Uninterested in his appearance, he usually wore the
(within 2%) by showing that no charge exists inside
same old lavender coloured coat.
66
Chadwick, Sir James

a charged hollow spherical conductor, a result ers when he was 10 years old. Cayley improved a
which is consistent only with that law. He worked helicopter-type toy (then known as a ‘Chinese top’)
on specific and latent heat (possibly knowing of and later made one which rose to 30 m, and he
Joseph Black’s work) and believed heat to stem devised model gliders powered by twisted rubber.
from ‘internal motion of the particles of bodies’. By 1799 he realized, ahead of all others, the basic
After 60 years of research, he chose (characteristi- problems of heavier-than-air flight and the relation
cally) to die alone. In his long lifetime this eccentric of the forces of lift, drag and thrust.
recluse achieved most in chemistry: notably in By 1804 he had made a whirling-arm device for
showing that gases could be weighed, that air is a testing purposes, and he saw the advantages of a
mixture and that water is a compound – all funda- fixed-wing aircraft design; other experimenters,
mental matters if chemistry was to advance. His for the rest of the century, focused on flapping-
work in physics was equally remarkable but was wing designs which, despite the example of birds,
largely without influence because much was were to prove a dead end. His experiments with
unpublished. The famous Cambridge physics labo- gliders were extensive and led him to a man-carry-
ratory named after him was funded by a talented ing design able to fly short distances. However,
mathematical kinsman, the 7th Duke of although he foresaw, correctly, that propulsion
Devonshire, in 1871. using a light engine driving a screw propeller was
Cayley, Arthur (1821–95) British mathematician: the way to success, no such light engine was then
developed n-dimensional geometry, and the theory available.
of matrices and algebraic invariants. His publications, which form the basis of aero-
Cayley, the son of an English merchant, spent his dynamics, appeared from 1809 to the 1840s. He also
first 8 years in Russia, where his father was then found time to serve as an MP, enjoy his 10 children
working. He was educated at King’s College School, and invent the caterpillar tractor, automatic sig-
London and Trinity College, Cambridge. Reluctant nals for railways, the self-righting lifeboat and the
to be ordained, which was a necessary condition to tension wheel, which he designed for aircraft
remain a Fellow of Trinity College, he became a bar- undercarriages and which is now most familiar in
rister. For 14 years he practised law, and only bicycles.
accepted the Sadlerian Chair of Pure Mathematics It was not until 1903 that the Wright brothers,
in Cambridge in 1863 when the requirement con- using Cayley’s ideas and adding their own talents,
cerning religious orders was dropped. were able to achieve effective powered heavier-
He managed to publish over 300 papers while a than-air flight; by then, a satisfactory light power
barrister and by his death he had published over unit, driven by petrol, could be made. As Wilbur
900, covering all areas of pure mathematics, theo- Wright wrote in 1909, ‘about 100 years ago an
retical dynamics and astronomy. While they were Englishman, Sir George Cayley, carried the science
both lawyers Cayley and his friend Sylvester estab- of flying to a point which it never reached before
lished the theory of algebraic invariants. and which it scarcely reached again during the last
Cayley also developed a theory of metrical geom- century’.
Celsius, Anders [selseeus] (1701–44) Swedish astro-
etry, linking together projective geometry and non-
Euclidean geometry. Together with Klein he nomer: devised Celsius scale of temperature.
classified geometries as elliptic or hyperbolic Celsius devised a thermometric scale in 1742,
depending on the curvature of space upon which taking the boiling point of water as 0° and the melt-
the geometry was drawn (that is, whether a surface ing point as 100°. Five years later, colleagues at
is saddle-like or dome-like). Uppsala observatory inverted the scale, to its pre-
The theory of matrices was an invention of sent (‘centigrade’) form.
Cayley’s and allowed compact manipulation of the In thermodynamics, temperatures are measured
many components of a geometrical system. The on the absolute or Kelvin scale. However, the
movement of a vector (directed line) when the Celsius scale is often used for other purposes, and is
space in which it is embedded is distorted can be now defined by the relation (temperature in °C) =
described by this theory. (temperature in K) – 273.15
Chadwick, Sir James (1891–1974) British physicist:
Cayley was a prolific mathematician with a
strong and dependable character, much in demand discoverer of the neutron.
both as a lawyer and administrator. Chadwick graduated in physics in Manchester in
Cayley, Sir George (1773–1857) British engineer: 1911 and stayed there to do research under
the founder of aerodynamics. Rutherford. He won an award in 1913 to allow
Cayley belongs to the group of gentleman ama- him to work with Geiger in Berlin, and when the
teurs, able to use their wealth and the peace of First World War began in 1914 he was interned.
country life to advance a scholarly enthusiasm. His Although held in poor conditions in a racecourse
school at York, and a clergyman tutor who trained stable for 4 years, he was able to do some useful
him as a mechanic and in mathematics, gave him research as a result of help from Nernst and others.
some skills needed for his later work, and his In 1919 he rejoined Rutherford, who had moved
teenage enthusiasm for models became a life-long to Cambridge, and for 16 years was to be his princi-
interest in flying. He knew of the first balloon pal researcher. Chadwick’s research with him was
mainly with alpha particles (helium nuclei 4 He);
flights, made in France by the Montgolfier broth- 2
67
Chain, Sir Ernst Boris

from the way these were scattered by heavier nuclei during the Second World War, studying sponta-
he could work out the positive charge of the scat- neous fission of heavy elements. After the war he
tering nucleus and show it to be the same as the conducted experiments with the bevatron particle
atomic number. They also used alpha particles to accelerator at Berkeley and in 1955, together with
bombard light elements and induce artificial disin- Segrè and others, discovered the antiproton, a new
tegration. Then, in 1932, he was able to reinterpret elementary particle with the same mass as the
an experiment reported by the Joliot-Curies, proton, but of opposite charge. Antiparticles had
which he saw as evidence for the existence of the been predicted theoretically by Dirac in 1926.
neutron (charge 0, mass 1), which Rutherford had Chamberlain and Segrè shared the 1959 Nobel
foreseen in 1920. Chadwick quickly did his own Prize for physics for their discovery.
Chandler, Seth Carlo (1846–1913) US geophysicist:
experiments to confirm his deduction; the neutron
allowed a massive advance in knowledge of atomic discovered variation in location of the geographic
nuclei and was one of a series of major discoveries poles (Chandler wobble).
in atomic physics made in the ‘marvellous year’ of By occupation both a scientist and an actuary,
1932, largely in Rutherford’s laboratory. Chandler became interested in the possible free
In 1935 Chadwick won the Nobel Prize for his dis- nutation (oscillation) of the Earth’s axis of rotation.
covery of the neutron, but soon afterwards friction By re-analysing repeated measurements of the lati-
with Rutherford arose because Chadwick wanted tudes of different observatories he discovered an
to build a cyclotron and Rutherford opposed this. annual variation in latitude (due to the motion of
Chadwick went to Liverpool as professor and soon air masses) and also another variation with a period
had his cyclotron (the first in the UK) and made the of roughly 14 months. Despite initially hostile reac-
department there a leading centre for atomic tion from the scientific establishment his conclu-
physics. When the Second World War came, he was sions were soon fully borne out. The cause of the
the natural leader of the UK’s effort to secure an secondary variation was subsequently explained
atomic bomb before the enemy succeeded in this. and it has since become known as the Chandler
Clearly the work had to be done in the USA, as the wobble – the apparent motion of the Earth’s axis of
UK was exposed to German bombing. Chadwick rotation across the Earth’s surface (detectable as a
made a masterly job of first propelling the work variation of latitude with time), with a period of
there into effectiveness, and then ensuring that approximately 14 months. It is caused by the pre-
collaboration proceeded smoothly. cession (or free nutation) of the Earth’s axis of sym-
Back in the UK after the war, advising govern- metry about its axis of rotation. For a rigid planet
ment on nuclear matters and increasingly doubtful the period would be exactly one year; the observed
of the wisdom of its policies, he had an unsatisfying slightly longer period, and its broad spectral peak
last phase in his career as Master of his old (428 ± 17 days), is due to elastic yielding of the
Cambridge college. Earth’s interior.
Chain, Sir Ernst Boris [chayn] (1906–79) German– Chandrasekhar, Subrahmanyan [chandrah-
British biochemist: member of the team which sayker] (1910–95) Indian–US astrophysicist: devel-
isolated and introduced penicillin for therapeutic oped theory of white dwarf stars.
use. Chandrasekhar studied in India and then in
Having studied physiology and chemistry in his Cambridge before moving to the USA in 1936.
native Berlin, Chain left Germany in 1933 and Chandrasekhar’s interest has been the final stages
worked in London and Cambridge. He joined of stellar evolution. He showed that when a star has
Florey’s staff in Oxford in 1935 and from 1938 exhausted its nuclear fuel, an inward gravitational
worked with him and Heatley on the production, collapse occurs, which will normally be eventually
isolation and testing of the mould product peni- halted by the outward pressure of the star’s highly
cillin, which by 1941 was shown to be a dramati- compressed and ionized gas. At this stage the star
cally valuable antibacterial. He shared a Nobel will have shrunk to become an extremely dense
Prize in 1945, moved to Rome in 1948 and returned white dwarf, which has the peculiar property that
to Imperial College, London in 1961. His work on the greater its mass, the smaller its radius. This
penicillin led him to discover penicillinase, an means that massive stars will be unable to evolve
enzyme which destroys penicillin; he later worked into white dwarves; this limiting stellar mass is
on variants of penicillin which were resistant to called the Chandrasekar limit and is about 1.4 solar
such destruction. Chain was a talented linguist and masses. It has been shown that all known white
musician, with forceful but unpopular views on the dwarves conform with this limit. Like his uncle, C V
organization of science. Raman, Chandrasekhar won a Nobel Prize, in 1983.
Chamberlain, Owen (1920– ) US physicist: dis- Chapman, Sydney (1888–1970) British applied
covered the antiproton. mathematician: developed the kinetic theory of
Chamberlain was educated at Dartmouth College gases and worked on gaseous thermal diffusion,
and the University of Chicago, and was appointed geomagnetism, tidal theory and the atmosphere.
professor of physics at the University of California Chapman studied engineering at Manchester and
at Berkeley 1958–89. mathematics at Cambridge, graduating in 1910.
Like many physicists at the time, Chamberlain During his career he held professorships in
worked on the Manhattan atomic bomb project Manchester, London and Oxford, and from 1954
68
Charnley, John

worked at the High Altitude Observatory, Boulder, value as a clue to the double helix structure for
CO, and the Geophysical Institute in Alaska. DNA put forward by Crick and Watson in 1953, in
Chapman’s interests were broad. He made a which the two helical nucleic acid strands are
notable contribution to the kinetic theory of gases, linked by bonds between complimentary bases,
taking the theory beyond the earlier work of adenine linking with thymine and cytosine linking
Maxwell and Boltzmann, to the Chapman–Enskog with guanine, by hydrogen bonds.
theory of gases. Chargaff’s relations with Watson and Crick were
Thermal diffusion refers to heat transfer between marked by mutual antipathy.
Charles, Jacques Alexandre CĂ©sar [shah(r)l]
two parts of a solid, liquid or gas that are at differ-
ent temperatures, in the absence of convection. He (1746–1823) French physicist: established tempera-
applied his theory to a variety of problems, notably ture–volume relationship for gases.
in the upper atmosphere. (Later, isotopes for Originally a clerk in the civil service, an interest
atomic fission were separated by use of gaseous in ballooning and the physics of gases together
thermal diffusion.) On geomagnetism, his other with a flare for public lecturing brought Charles
main interest, he investigated why the Earth’s mag- fame, and ultimately a professorship of physics in
netic field varies with periods equal to the lunar Paris.
day (27.3 days) and its submultiples; he showed this In 1783, together with his brother Robert, Charles
was due to a tidal movement in the Earth’s atmos- made the first manned ascent in a hydrogen bal-
phere due to the Moon. The Chapman–Ferraro loon, a feat which brought him considerable public
theory of magnetic storms predated modern acclaim. On a later flight he was to reach an alti-
plasma theory. He also studied the formation of tude of 3000 m. His interest in gases subsequently
ozone in the atmosphere and the ionizing effect of led him to formulate Charles’s Law in 1787, that
solar ultraviolet light on the ionosphere (the the volume of a given amount of gas at constant
Chapman layer being named for him). In his later pressure increases at a constant rate with rise in
years he developed, with S I Akasofu (1930– ), the temperature. Further experimental work by Gay-
modern theory of geomagnetic storms, the ring Lussac and Dalton confirmed the relationship,
current and the aurora. which holds best at low pressures and high tem-
Charcot, Jean-Martin [sha(r)koh] (1825–93) French peratures (ie it applies to ideal gases). Incidentally,
neurologist: related many neurological disorders Amontons had also discovered the relationship
to physical causes. almost a century before but, failing to publicize the
Charcot was born and studied medicine in Paris, fact, did not receive the credit for it.
Charney, Jule Gregory (1917–81) US meteorolo-
and spent his career at its ancient and famous hos-
pital, the Salpêtrière. Appointed there in 1862, he gist: pioneer of numerical techniques in dynamic
found it full of long-stay patients with diseases of meteorology.
the nervous system about which little was known. Charney’s work was principally concerned with
By careful clinical observation and later autopsy he dynamic meteorology. In 1947 he analysed the
was able to relate many of their conditions with problem of the formation of mid-latitude depres-
specific lesions; for example the paralysis of polio sions, in particular the dynamics of long waves in a
with the destruction of motor cells in the spinal baroclinic westerly current. He went on to work on
cord; the paralysis and lesions of cerebral haemor- numerical methods of weather prediction with
rhage; and a type of arthritis with neurosyphilis. He Von Neumann, developing a system of quasi-
was the major figure in the Paris Medical School for geostrophic prediction equations and the concept
many years and his many pupils included Sigmund of the ‘equivalent barotropic level’. Charney also
Freud (1856–1939), who developed Charcot’s spe- tackled problems concerned with the flow of the
cial interest in hysteria. After his death his only Gulf Stream, the formation of hurricanes and the
son, Jean, gave up medicine and became the lead- large-scale vertical propagation of energy in the
ing French polar explorer. atmosphere.
Chargaff, Erwin [chah(r)gaf] (1905– ) Czech–US bio- Charnley, John (1911–82) British orthopaedic sur-
chemist: discovered base-pairing rules in DNA. geon who devised a satisfactory replacement hip
Chargaff studied at Vienna, Yale, Berlin and Paris, joint.
and worked in the USA from 1935 at Columbia Charnley’s parents were a pharmacist and a
University, New York. His best-known work is on nurse, so it is unsurprising that he studied medi-
nucleic acids. By 1950 he had shown that a single cine. He specialized in orthopaedic surgery, quali-
organism contains many different kinds of RNA fied young and operated throughout his life in the
but that its DNA is of essentially one kind, charac- Manchester area where he had always lived.
teristic of the species and even of the organism. The His career was dominated by one problem, the
nucleic acids contain nitrogenous bases of four treatment of the painful and disabling condition of
types: adenine, thymine, guanine and cytosine. osteoarthritis of the hip joint, common in the
Chargaff showed that the quantities of the bases elderly. Until his success in the 1960s surgical
are not equal, as some had thought, but that, if we reconstruction of this joint was, in his words, ‘no
represent the number of the respective bases in a great credit to orthopaedic surgery’. In the 1950s he
DNA by A, T, G and C respectively, then (very nearly) set up a workshop in the attic of his home and a bio-
A = T, and C = G. These Chargaff rules were of great medical testing laboratory at the Wrightington
69
Charpak, Georges

Hospital. His systematic studies on possible replace- retreat at the du Châtelet estate at Cirey-sur-Blaise,
ment joint materials and their friction and lubrica- where they established a laboratory. Cirey became
tion led him, by 1963, to settle on a replacement the French centre of Newtonian science, with du
joint consisting of a socket made of the then novel Châtelet providing Voltaire with the mathematical
plastic HMWP (high molecular weight polyethyl- expertise he lacked. In Institutions de physique (1740),
ene) in which moved a rather small polished steel written as a textbook for her son, she tried to rec-
head which replaced the diseased head of the oncile Newtonian and Leibnizian views. In 1744 she
patient’s femur. Both were fixed into the bone with began a translation of Newton’s Principia mathe-
acrylic cement. Charnley’s procedure, widely used matica, which remains a standard version. At the
by him and others, transformed many lives. age of 42 she became pregnant again and, fearing
Charpak, Georges (1924– ) Polish–French physi- that she would not survive the birth of her child,
cist: inventor of multiwire and drift particle she worked long hours, taking little sleep; she died
detectors. of puerperal fever. She had deposited the manu-
Charpak was born in Poland and became a natu- script with the librarian of the Bibliothèque du Roi
ralized French citizen at the end of the Second in Paris; it was published in 1759. Emilie
World War. He studied as a mining engineer before du Châtelet’s work, which made Newtonian and
taking a PhD in experimental nuclear physics at the Leibnizian ideas available in France, was followed
Collège de France, and working at the CNRS. From by strong development of celestial mechanics
1959 he worked at CERN and in 1968 published his there.
Chatelier, Henri Louis Le see Le Chatelier
invention of the multiwire proportional counter,
Cherenkov, Pavel Alekseyevich [cherengkof]
which later won him the Nobel Prize. A problem for
particle physicists is that it is often only one inter- (1904–90) Russian physicist: discoverer of the
action in a billion that is of interest, and selection Cherenkov effect.
from photos of events in bubble chambers and A graduate of Voronezh State University, Cheren-
the like was too time-consuming. Charpak began kov worked at the Lebedev Institute of Physics from
instead with the Geiger MĂĽller tube or proportional 1930. In 1934 he first saw the blue light emitted
counter which uses a single wire at the centre of a from water exposed to radioactivity from radium,
"1 cm diameter tube, with a strong electric field which had been observed by many earlier workers
between the two. A particle causes an avalanche or who had assumed it to be fluorescence. Cherenkov
cascade of ionization, registered as a click of cur- soon found that this could not be the explanation
rent, an electronic response. Charpak produced a because the glow is shown by other liquids; and he
sheet-like multiwire proportional detector using found it was caused by fast electrons (beta rays)
fine wires about 2 mm apart, between two sheets of from the radium and that it was polarized. By 1937,
closely spaced wires at a strong negative potential. working with I M Frank (1908–90) and I E Tamm
He then obtained a similar response from a cell of (1895–1971), he was able to explain the effect. They
the detector when a particle passed, due to a local- showed that in general the effect arises when a
ized cascade. The signals were amplified and fed charged particle traverses a medium (liquid or
directly into a computer, which registered and solid) when moving at a speed greater than the
sifted the many particles, at high speed. This inven- speed of light in that medium, and they were able
tion and its variants formed the basis for virtually to predict its direction and polarization. The effect
all particle detection made since, and allowed dis- is dramatically visible in the blue glow in a ura-
covery of the charm quark in 1974 (by Richter and nium reactor core containing heavy water; and it is
Ting) and the intermediate boson in 1983 (by used in a method for detecting high-energy
Rubbia and van der Meer). charged particles. A counter of this type, using a
Châtelet-Lomont, Gabrielle-Emilie, marquise photomultiplier, can detect single particles. The
(Marchioness) du, née le Tonnelier de Breteuil effect has some analogy with the shock wave and
[shatuhlay lohmõ] (1706–49) French writer on sonic boom produced when an aircraft exceeds the
physics and mathematics. speed of sound in air. Cherenkov, Frank and Tamm
The youngest child of the chief of protocol at the shared a Nobel Prize in 1958.
Chevreul, Michel Eugène [shevroei] (1786–1889)
court of Louis XIV, Emilie de Breteuil was born into
an aristocratic society that expected its women to French organic chemist: investigated fats and nat-
be beautiful, intelligent and witty. As she was con- ural dyes.
sidered too tall (175 cm/5 ft 9 in), her father A surgeon’s son, Chevreul learned chemistry as
believed she would remain single and, unusually assistant to Vauquelin, and by 1824 became direc-
for the period, provided her with the best tutors. tor of dyeing at the famed Gobelins tapestry fac-
Her marriage (1725) survived a succession of lovers, tory. His best-known work is on animal fats, which
lawsuits and separations; her husband owned a he showed by 1823 could be separated into pure
number of large estates, had a passion for war and individual substances that, with acid or alkali,
was frequently absent. After the birth of her third break down to give glycerol and a fatty acid. (The
child Emilie du Châtelet began serious studies in fatty acids were later shown to be long-chain mono-
Newtonian physics with P L de Maupertuis (1698– carboxylic acids.) Chevreul showed that soap-
1759) and A-C Clairaut (1713–1765). She became the making (saponification) of animal fats by alkali
mistress of Voltaire and provided him with a safe could be understood and improved chemically, and
70
Clausius, Rudolf

that soaps are sodium salts of fatty acids. In 1825
Chevreul with Gay-Lussac patented a method of
making candles using ‘stearin’ (crude stearic acid)
in place of tallow, which was odorous, less lumi-
nous and unreliable; when developed, the improve-
ment was of substantial importance. Chevreul
showed that the urine of diabetic patients con-
tained grape-sugar (ie glucose). He worked on
organic analysis and the chemistry of drying oils
(used in paints), on waxes and natural dyes; on the-
ories of colour; on the use of divining rods and
(after he was 90) on the psychological effects of
ageing. As a child of 7, he had watched the guillo-
tine in action; after his centenary, he watched the
construction of the Eiffel Tower. He never retired.
Clarke, Sir Arthur Charles (1917– ) British inven-
tor of the communication satellite and science
fiction writer.
Very few individuals have single-handedly
devised a technical advance of world-wide impor-
tance; to combine this in one career as a leading sci-
ence fiction writer is not only exceptional but
unique. A radar instructor in the Second World
War, Clarke published a seminal article in 1945 Rudolf Clausius
in the popular non-academic technical journal
Wireless World, outlining a full scheme for a novel higher to a lower temperature, he also believed
concept, the communication satellite. He deduced that it passed through the engine intact. The First
that the satellite must be in a geostationary orbit (ie Law of Thermodynamics, largely due to Joule, visu-
centred over a fixed earthly location) at a precise alizes some heat as being lost in a heat engine and
distance, which he calculated. The first such satel- converted into work. This apparent conflict was
lite was in use in 1964, and by the late 1980s over solved by Clausius, who showed in 1850 that these
400 satellites in Clarke orbits had been launched, results could both be understood if it is also
and were transmitting 4000 million telephone calls assumed that ‘heat does not spontaneously pass
annually and linking TV transmissions in 100 coun- from a colder to a hotter body’ (the Second Law of
tries. After a science degree in London, Clarke Thermodynamics). The next year W Thomson
wrote the non-fictional The Exploration of Space arrived at the same law, differently expressed, and
(1951); but thereafter his novels made him best there are now several other equivalent formula-
known as a writer of science fiction. As co-writer of tions of the same principle. Clausius developed this
the film 2001: A Space Odyssey he had a major success concept, of the tendency of energy to dissipate, and
in the genre in 1968. In this film he foresaw space in 1865 used the term entropy (S) for a measure of
stations, financed internationally; other forecasts the amount of heat lost or gained by a body, divided
by Clarke, made a full generation before they by its absolute temperature. One statement of the
became a reality, include a manned moon-landing, Second Law is that ‘the entropy of any isolated
reusable space vehicles, on-board car navigation system can only increase or remain constant’.
aids, and moving walkways at airports. From 1956 Entropy was later seen (eg by Boltzmann) as a mea-
he lived in Sri Lanka. He was knighted in 1998. sure of a system’s disorder. The Second Law gener-
Clausius, Rudolf [klowzeeus] (1822–88) German ated much controversy, but Clausius, Maxwell and
theoretical physicist: a founder of thermodynam- Thomson led a vigorous and successful defence,
ics, especially linked with its Second Law. although we would not now fully accept Clausius’s
Clausius’s father was a Prussian pastor and pro- crisp summaries of ‘the energy of the universe is
prietor of a small school which the boy attended. constant’ (First Law) and ‘the entropy of the uni-
Later he went to the University of Berlin to study verse tends to a maximum’ (Second Law), thereby
history, but changed to science; his teachers predicting a ‘heat-death’ for the universe.
included Ohm and Dedekind. He was short of Clausius also did valuable work on the kinetic
money, which delayed his graduation, but his theory of gases, where he first used the ideas of
ambition was to teach university physics and he did ‘mean free path’ and ‘effective molecular radius’
so at ZĂĽrich, WĂĽrzburg and Bonn. In the Franco- which later proved so useful. In the field of elec-
Prussian War of 1870 he and his students set up an trolysis, Clausius was the first to suggest (in 1851)
ambulance service and he was badly wounded. that a salt exists as ions in solution before a current
By the 1850s a major problem had arisen in heat is applied. In each area he attacked, he showed out-
theory: Carnot’s results were accepted, but while standing intuition, and his work led to major devel-
he believed correctly that, when a heat engine pro- opments by others; but Clausius was strangely little
duces work, a quantity of heat ‘descends’ from a interested in these developments.
71
Cockcroft, Sir John Douglas

Cockcroft, Sir John Douglas (1897–1967) British tury earlier but never made effective. Cockerell had
physicist: pioneered the transmutation of atomic some success with models by 1955, and later the
nuclei by accelerated particles. flexible skirt was devised, which retained a cushion
Cockcroft had completed only his first year at of air well enough to give the first satisfactory hov-
Manchester University when the First World War ercraft. A prototype (the SR-N1) built by the
broke out and he joined the Royal Field Artillery as Saunder–Roe Company was completed in 1959; it
a signaller. Remarkably he survived unscathed weighed 7 tonnes and achieved manned crossings
through 3 years and most of the later battles. of the English Channel at speeds up to 95 kph/
Afterwards, he studied electrical engineering at 60 mph. Although hovercraft afterwards had some
Manchester and then joined the Metropolitan commercial success, their use has been more limited
Vickers Electrical Company and took his degree at than was initially expected.
Cohn, Ferdinand Julius (1828–98) German botanist
Cambridge in mathematics (1924). He then became
part of Rutherford’s research team at the and bacteriologist.
Cavendish and in 1932 made his reputation by a Cohn was a precocious child and, despite the dif-
brilliant experiment with E T S Walton (1903–95), ficulties caused by German antisemitic rules, he
for which they received the 1951 Nobel Prize for was awarded a doctorate at Berlin for his work in
physics. botany when he was 19. He returned to his home
Cockcroft was methodical in his work, genial and city of Breslau (now in Poland) and became profes-
decisive, and no waster of words. He soon became sor of botany there in 1872. A keen microscopist, he
mainly interested in research management, and in came to the important conclusion that the proto-
1940 was a member of the Tizard Mission to the plasms (cell contents) of plant and animal cells are
USA to negotiate wartime technological exchange. essentially similar. He was the first to devise a sys-
He then became head of the Air Defence Research tematic classification for bacteria and did much to
and Development Establishment (1941–4). He was define the conditions necessary for bacterial
also Jacksonian Professor at Cambridge (1939–46). growth.
Cohnheim, Julius [kohnhiym] (1839–84) German
He became founding director of the Atomic Energy
Research Establishment at Harwell (1946) and led pathologist: a pioneer of experimental pathology.
the establishment of the Rutherford High-Energy A graduate in medicine from Berlin, Cohnheim
Laboratory at Harwell (1959). In 1959 he became became an assistant to Virchow and was probably
founding Master of Churchill College, Cambridge. his most famous pupil. He attracted many students
Receiving many honours, Cockcroft became a lead- himself, as a teacher of pathology at Kiel, Breslaw
ing statesman of science, combining research and and finally Leipzig. His early work was in histology:
administrative skills. soon after graduating he devised the freezing tech-
The experiment conducted by Cockcroft and nique for sectioning fresh tissue and later a method
Walton was triggered by Gamow mentioning (1928) of staining sections with a solution of gold. From
to Cockcroft that bombarding particles may enter a 1867 he published a masterly series of studies on in-
nucleus by quantum mechanical ‘tunnelling’. This flammation; he showed by experiments with frogs
could occur at much lower incident energies than how blood vessels responded in its early stages and
those required to overcome Coulomb repulsion proved that the leucocytes (white cells) pass through
between the two. Using skilfully built voltage- the walls of capillaries at the site of inflammation
doublers, protons were accelerated to 0.8 MeV and and later degenerate to become pus corpuscles.
directed at a lithium target. Alpha particles Mechnikov and others were later to confirm and
(helium nuclei) were found to be released; the first extend these studies.
artificially induced nuclear reaction (transmuta-
tion) was occurring; and was later shown to be:
Li + 1H → 4He + 4He (+ 17.2 MeV)
7 rudders
lift-fan air intake
3 1 2 2
(In his experiments on transmutation, Ruther- tailfins
propellers
ford had used, as projectiles, particles from a nat-
ural radioactive source.) With the publication of control cabin
this exciting result the nuclear era began, and
cyclotrons and linear accelerators were built to
study nuclear physics.
Cockerell, Sir Christopher Sydney (1910–99)
British engineer: inventor of the hovercraft.
A Cambridge graduate in engineering, Cockerell’s
early career was in radio, with the Marconi
Company from 1935 and working there mainly on
air
fan hull skirt
radar in the Second World War. Leaving them in
skirt
1950 for a new career in commercial boat building
Water
and hiring, he turned to the long-studied problem
cushion of air
of reducing drag on boat hulls. Both theory and his
early experiments pointed to an air-cushion as a
possible answer, an approach first considered a cen- Hovercraft – inset shows method of operation
72
Columbus, Christopher

Despite evidence, tuberculosis (then a major cause wealthy ship’s outfitters prepared his flagship
of death in Europe) was not easily accepted as infec- Santa Maria at their own expense and in August
tious. Cohnheim provided new and convincing evi- 1492 he sailed in her from Palos near Huelva in
dence by injecting tuberculosis matter into the southern Spain, with the Pinta and Niña also under
chamber of a rabbit’s eye and then observing the his command, a total of about 100 men and a letter
tuberculous process through its cornea. He also from the Spanish sovereigns to the ‘grand khan of
studied heart disease, examining obstruction of China’.
the coronary artery and deducing correctly that the The fleet went south to the Canary Islands and
resulting lack of oxygen led to myocardial damage then due west, making landfall in the Bahamas in
(infarction). This work was reviewed and the condi- October 1492 after a 5-week voyage from the
tion named as ‘coronary thrombosis’ by J B Herrick Canaries. Columbus’s difficulties had included
(1861–1954) in 1912. maintaining the confidence of his crews and solv-
Colombo, Matteo Realdo (c.1516–59) Italian ing his navigational problems; these arose in part
anatomist: a discoverer of the lesser circulation of from the deviation of the magnetic compass from
the blood. true north, which he may have been the first to
Son of an apothecary, Colombo was a student of observe.
anatomy, medicine and surgery under Vesalius From the Bahamas Columbus sailed to Cuba,
and succeeded him at Padua and Pisa. In his book which he thought was Japan, and believed he could
On Anatomy (1559) he gives more modern descrip- soon reach China: then west to Haiti, where he
tions (without illustrations) than earlier anatomists. began a settlement and traded with the native pop-
He describes the lens at the front of the eye (not in ulation. The Santa Maria was lost, a party was left in
the middle, as earlier anatomists had believed) and Haiti to study its inhabitants and their produce and
the pleura and peritoneum. He describes clearly Columbus sailed for Spain in January 1493 still con-
the lesser circulation through the lungs, and in a vinced he had been in Asia. He was back in Palos in
vivisection on a dog he cut the pulmonary vein and March to an enthusiastic welcome, bringing from
showed that it contained blood and not air; and its the West Indies new plants and animals, a little
bright red colour made him believe that the lungs gold and six natives.
had made it ‘spiritous’ (ie oxygenated) by air. He did Returning to Haiti in September with a much
not understand the general circulation, as Harvey enhanced expedition, he found his settlement
did later. destroyed and the men killed, but he sailed on to
Columbus, Christopher, Cristoforo Colombo discover Jamaica before returning to Spain in 1495,
(Ital), Cristóbal Colón (Span) (1451–1506) Italian leaving his brother Bartolomeo in charge of a
explorer: first nameable discoverer of the New restored colony in Haiti. He found that his prestige
World. in Spain had fallen, largely because the commercial
The eldest of the five children of a weaver, profits on the first voyage was less than extravagant
Columbus probably first entered his father’s trade, hopes had foreseen, so that his third expedition, in
but before 1470 he went to sea and for some years 1498, was on a reduced scale in men and ships.
voyaged and traded for various employers based in Nevertheless, it led to his discovery of Trinidad and,
Genoa, his birthplace. His work took him to notably, of the South American mainland, the coast
England in 1477, and probably to West Africa in of Venezuela. In 1500 a newly appointed royal
1482, and about this time he began to seek finan- govenor visited him, was critical of affairs in the
cial support for a major Atlantic expedition. colony and sent Columbus back to Spain in irons.
Classical writers (including Aristotle, Ptolemy Tensions had arisen, in part because the ‘gentle-
and Pliny) had accepted that the Earth was spheri- man adventurers’ who had accompanied Columbus
cal, and so it followed that China and Japan (known not only traded but, unlike him, took gold and girls
through the Polo family’s descriptions) could be by force. They resented the fact that Columbus and
reached by sailing west. In accepting this idea, his brothers were not Spanish, and they accorded
Columbus made two major errors. Firstly, he no rights to the natives because the latter were not
believed the Asian landmass to extend more to the Christians. Indiscipline had reached the point
east than is actually the case. Also he estimated the where some Spaniards had been hanged, and the
Earth’s radius at only three-quarters of its true new governor viewed the whole situation as highly
value. As a result, he believed Japan to be located unsatisfactory.
in roughly the position where the West Indies Fortunately the Spanish sovereigns repudiated
are placed. Aside from these miscalculations, Columbus’s disgrace, restored him to favour and
Columbus was a very competent navigator and he supported his fourth and last great voyage in 1502,
and one of his brothers had a business as chart- during which he explored the southern coast of the
makers. Gulf of Mexico in search of a passage to Asia, which
For some years Columbus failed to obtain support he still believed to be nearby. Much hardship and dif-
for a transatlantic expedition but in March 1492 ficulty arose and this objective was inevitably not
the catholic monarchs of Spain, Isabella and attained; but the coast of Central America was exten-
Ferdinand, approved his voyage and awarded him sively explored, until hostile natives and disease
the title of Admiral of the Ocean Sea and the gover- forced Columbus to take refuge in Jamaica, with his
norship of any new land he might discover. Two ships in a poor state and their crews mutinous. In
73
Compton, Arthur Holly

1504 he returned to Spain dispirited and ill, still Compton developed an ionization chamber for
ignorant of the real nature of his discoveries. He died detecting cosmic rays and in the 1930s used a world-
in 1506 at Valladolid and his remains, after several wide survey to demonstrate that cosmic rays are
removals and confusions, were interred at Seville in deflected by the Earth’s magnetic field and some
1902 in a mausoleum, honoured for something he are therefore charged particles (and not radiation).
had not meant to do and never knew he had done. Variation of ray intensity with time of day, year and
An authentic portrait of him probably does not the Sun’s rotation also indicated that the cosmic
exist, but he is known to have been tall and red- rays probably originate outside our Galaxy (1938).
haired. In personality he was eccentric, impetuous, In 1941 Compton was asked to take part in feasi-
highly religious and driven by social ambition and bility studies and the development of plutonium
the pursuit of gold. His explorations fall within a production for the atomic bomb. His religious faith
period of great discoveries: in 1487 Diaz had made him question what was happening, but he
rounded the Cape of Good Hope; in the 1490s felt that only such a weapon would quickly end the
Columbus explored the West Indies, Central massive slaughter of the war. He became director of
America and parts of South America; in 1498 da a major part of the Manhattan Project at Chicago
Gama reached India; and by 1521 Magellan had and built the first reactor with Fermi (1942), pub-
crossed the Pacific and circumnavigated the Earth. lishing an account in his book Atomic Quest (1958).
In only 35 years all the previously unknown oceans (Portrait on p. 170)
Cook, James (1728–79) British explorer: founder of
were crossed, and the existence of the continents
was proved except for Australia and Antarctica, modern hydrography and cartography; explored
with Portugese seamen, inspired by Prince Henry the Pacific and showed that scurvy was preventable
‘the Navigator’ taking leading parts. on a long voyage.
Columbus’s credentials as a scientist are modest, The son of an agricultural labourer, Cook joined
but he remains without a peer as a mariner and as the Royal Navy in 1755 and was given his own com-
discoverer and explorer of new islands and, mand 2 years later. He is remembered for his voy-
unknowingly, of a New World which he was the ages of discovery, which transformed knowledge of
first to link with the Old. the Pacific and set the pattern for the great scien-
Compton, Arthur Holly (1892–1962) US physicist: tific expeditions of the 19th-c. After much hydro-
discovered the Compton effect concerning the graphic work of the highest quality, Cook was
wavelength of scattered photons. charged with taking the Endeavour to Tahiti in 1768
Compton was the son of a Presbyterian minister with observers (including Banks) for the transit of
who was also a professor of philosophy, and inher- Venus, on behalf of the Royal Society. At that time
ited a deep religious faith from him. He obtained observations of transits of inner planets across the
his doctorate at Princeton, and spent two years face of the Sun were one of the principal means of
with Westinghouse Corporation. On travelling to estimating the Earth–Sun distance. Cook went on
Britain he spent a year doing research under to chart the east coast of Australia and the coast of
Rutherford at Cambridge before returning to New Zealand, showing it to consist of two main
America as head of the Physics Department at islands, and his voyage set an upper limit to the size
Washington University, St Louis, MO (1920). A pro- of any possible southern continent. Both for this
fessorship at Chicago followed in 1923. In 1945 he voyage and his second expedition, the Admiralty’s
returned to Washington as chancellor. secret orders to Cook required him to explore the
In 1923 Compton observed that X-rays scattered South Pacific where they had ‘reason to imagine
by passing through paraffin wax had their wave- that a continent, or land of great extent, may be
length increased by this scattering. Compton and found’, and ‘to take possession of it in the King’s
Debye explained this in detail, stating that photons name’. These expeditions had both scientific and
(electromagnetic waves) behave as particles as well political objectives. Cook’s second expedition in
as waves; they lose energy E and momentum on 1772–5 further delineated the possible extent of
making elastic collisions and as Antarctica and also demonstrated that fresh fruit
E = hc/λ and vegetables were all that were needed to prevent
where c is the speed of light, their wavelength λ scurvy, a major problem on long sea voyages at the
increases. Here h is Planck’s constant. Compton time. (See panel opposite.)
found tracks in photographs taken in a Wilson In 1776 he was made a Fellow of the Royal Society.
cloud chamber, showing electrons recoiling from His last expedition, begun in 1776, was intended to
collisions with the invisible (because uncharged) discover a northern route between the Atlantic and
photons of an X-ray beam. This work established the Pacific but ended in his tragic death when he was
Einstein’s belief that photons had energy and attacked by natives in Hawaii.
momentum, and also Broglie’s assertion (1925) Improved sextants and other instruments, and
that in quantum mechanics objects display both especially Cook’s talent and energy, ensured that
wave and particle properties. Compton and C T R more survey work and scientific research was done
Wilson received the 1927 Nobel Prize for physics by him than by any previous expeditions. Modern
for their work, which is now part of the foundation maps of the Pacific with its coasts and islands
of the new quantum theory (as opposed to Bohr’s owe much to him, and he set new standards of
old quantum theory). cartography and hydrography.
74
Panel: The Exploration of Australia


THE EXPLORATION OF AUSTRALIA Murray rivers between 1829–30, but failed to find the
inland sea which he believed to exist west of the
Australia was first colonized from Asia at least Darling. Thomas Livingstone Mitchell (1792–1855)
40 000 and probably 100 000 years ago, but it discovered the rich grazing lands of Victoria, which he
remained unknown to Europeans until the east coast called Australia Felix, and settlers moved into them to
was charted by Portuguese sailors during the 1520s. raise ever-increasing numbers of sheep.
Abel Janszoon Tasman (1603–c.1659) made two Settlements had already been established in
voyages to Australia, in 1642 and 1644. He was the Western Australia, and much energy was expended on
first person to discover Tasmania (which he named trying to find a practical stock route between South
after the Governor of Batavia, Antony Van Diemen) Australia and Western Australia. Finally, in 1840–1,
and New Zealand. However, he failed to discover Edward John Eyre (1815–1901) established that there
whether Australia was an island or not, or what the was no such route, but discovered Lake Eyre and Lake
relationship was between the pieces of land he had Torrens in the process. Later in the decade, Ludwig
discovered. Leichhardt (1813–c.1848) explored the coastal region
The major work of charting Australia and New of N Queensland and the Northern Territory. His
Zealand was carried out by COOK. On his first voyage methods were somewhat haphazard, and he disap-
(1768–70), he charted the coast of New Zealand and peared in 1848 while on an expedition into the interior
the entire east coast of Australia. He landed on of Queensland. No trace of his party has ever been
Possession I off the tip of Cape York on 22 August found.
1770, and claimed the east coast for Britain under the The fate of Leichhardt illustrated that Australia was
name of New South Wales. BANKS sailed as a botanist not a safe place for inexperienced and ill-prepared
with Cook, and was later largely responsible for the explorers. The most disastrous expedition was that, in
establishment of the Botany Bay penal colony. 1861, of Robert O’Hara Burke (1820–61) and William
The first fleet landed in Botany Bay during Cook’s John Wills (1834–61) who managed to cross Australia
third voyage, on 26 January 1788, commanded by S–N with relative ease, because it was an unusually wet
Arthur Phillip, first Governor of New South Wales. season; but having left most of their supplies at base
Expeditions were sent to fill in the gaps in the charts camp, they died of starvation on the way back. The sole
of the coastline. George Bass (? –1812) circum- survivor of the expedition, John King (1838–72), was
navigated Tasmania in the late 1790s, while his the only one to accept help offered by local Aborigines.
associate Matthew Flinders (1774–1814) later The fate of Burke and Wills encouraged other
charted the coastline of South Australia and, during explorers of the centre of Australia to be much more
1801–3, was the first person to circumnavigate the cautious. Over the course of several years (1858–60),
continent. John McDouall Stuart (1815–66) established a
During the governorship of Lachlan Macquarie, the practical route S–N, supplied throughout with water-
interior of New South Wales was explored by William holes and passing by Alice Springs. Further explo-
Charles Wentworth (1793–1872) and other explorers ration of the centre was carried out by Peter Egerton
were quick to follow into the depths of the continent. Warburton (1813–89) and John Forrest (1847–1918,
During 1824–5 Hamilton Hume (1797–1873) discov- later premier of Western Australia), and especially by
ered the Murray River, and in 1827 Allan Cunningham William Ernest Powell Giles (1835–97) who crossed
(1791–1839) carried out a good deal of exploration of the centre of Australia twice (1875–6), travelling E–W
the remoter parts of New South Wales in the search for and back again.
botanical specimens. Charles Sturt (1795–1869),
Sukie Hunter
together with Hume, discovered the Darling and lower


Coolidge, William David (1873–1975) US physicist fragility of the wire. Coolidge found that the answer
and chemist. was to limit the crystallinity of the metal by precise
Coolidge studied electrical engineering at MIT, control of manufacturing conditions, to secure it in
physics at Leipzig, and chemistry on his return to a ductile form that could be drawn into wire
MIT. With this highly suitable background he through diamond dies at 550°C. Lamps using the
joined GEC’s research lab at Schenectady in 1905: he wire cut the cost of electric light to that of gas-light
became its Director in 1932. In a long active career by 1914, with GEC dominating the market. Before
he made two outstanding innovations, both involv- that date Coolidge had vastly improved X-ray tubes,
ing the high-melting metal tungsten. The first was to the level where they became routinely manage-
the use of it for the filaments of electric lamps. able for clinical use. In place of a cold aluminium
Edison used carbon for this, but the life and effi- cathode, his tubes used a hot tungsten cathode as
ciency of carbon filaments were both low: it was target for the electrons from a hot filament, with a
clear that tungsten should be better (m.p. 3380°C), lowered gas pressure and controlled cooling. His
but early attempts failed because of the brittle participation in allied science linked with both
75
Cooper, Leon Neil

observations, he showed that a cosmology in which
Earth and the planets rotate about the Sun offered
a simpler explanation of planetary motions than
the geocentric model of Ptolemy, which had been
universally accepted for well over 1000 years. He
circulated his preliminary ideas privately in a short
manuscript in 1514 and continued to develop the
theory over the next 30 years. Among his sugges-
tions was the idea that the fixed stars were much
further away than had previously been thought
and that their apparent motion at night (and the
Sun’s motion by day) was due to Earth’s daily rota-
tion about its axis, but he retained the conven-
tional idea that the planets moved in perfectly
circular orbits. His ideas were first fully described
in his book De revolutionibus orbium coelestium (The
Revolution of the Heavenly Spheres) which, although
complete by 1530, was not published until 1543.
Copernicus himself may only have seen the pub-
lished book on the day he died.
Copernicus’s ideas were immediately criticized
by other astronomers, notably Brahe, who argued
that if the Earth was moving then the fixed stars
Nicolaus Copernicus: one of many similar engravings, all ought to show an apparent movement by parallax
said to be based on a self-portrait. also. Copernicus’s answer to this, that the stars
were too far away for parallax to be apparent, was
World Wars and included viewing the Bikini atoll rejected on the grounds that it was inconsistent
atom bomb tests in 1946. with the accepted size of the universe. The idea of a
Cooper, Leon Neil (1930– ) US physicist: con- moving Earth was also hard to accept. The Church
tributed to BCS theory of superconductivity. later officially banned De revolutionibus in 1616 and
Leon Cooper was educated at Columbia Univer- did not remove it from its Index of Forbidden Books
sity, obtaining his doctorate in 1954. He collabo- until 1835.
rated with Bardeen and Schrieffer at Illinois on Copernicus’s view that the Sun was the centre of
the BCS theory of superconductivity. the solar system gained credence from Galileo’s
Soon after his doctoral work in quantum field work on Jupiter’s moons in 1609; but the parallax
theory, Cooper made a theoretical prediction of the of a fixed star was not measured until 1838 by
existence of bound pairs of electrons at low tem- Bessel. However, the idea of a heliocentric (Sun-
perature. Although two electrons repel each other, centred) system, with a moving Earth, had been
they may behave differently in a solid with a sea of accepted as a reality and not a mere mathematical
electrons with an embedded lattice of positive ions. device long before that; and Copernicus’s circular
One electron distorts the lattice, pulling it in about orbits for planets had been replaced by Kepler’s
it, and the other electron is attracted to the locally elliptical orbits by 1609. The ‘Scientific Revolution’
higher concentration of positive ions. This effect is often dated from Copernicus’s work, reaching its
can be imagined from the similarity to two can- climax with Newton about 150 years later. In the
nonballs on a mattress rolling together into the same year (1543) that Copernicus’s De revolutionibus
same depression. Thus at low temperature, when appeared, Vesalius’s book On The Structure of the
thermal vibrations do not disturb this process, Human Body was published; men’s views of nature
bound pairs (called Cooper pairs) of electrons form. were changing fast. (See panel on p. 78.)
Corey, Elias J (1928– ) US organic chemist: devisor
The BCS theory then accounts for superconductiv-
ity as being due to the fact that these pairs can of retrosynthetic analysis, and synthesizer of nat-
move through a lattice with zero scattering by ural products and new therapeutic agents.
impurities because the pair is much larger than any All of Corey’s grandparents had emigrated from
impurity atom. For this work Bardeen, Cooper and the Lebanon to the USA, under pressure as
Schrieffer shared the 1972 Nobel Prize for physics. Christians to leave the Ottoman Empire of that
Copernicus, Nicolaus, Mikolaj Kopernik (Pol) time. As a child he lived in a household with his
[kopernikuhs] (1473–1543) Polish astronomer: pro- early-widowed mother, and three siblings, and his
posed heliocentric cosmology. mother’s childless sister and her husband. Rather
Copernicus was the nephew of a prince bishop. happily carefree and sports-oriented, Corey credits
Having studied mathematics, law and medicine in his aunt with ensuring that all four children could
Poland and Italy, Copernicus was for most of his life concentrate on work as well as leisure; and he
a canon at Frauenburg Cathedral, his duties being entered MIT aged 16 to study chemistry, physics
largely administrative. Working mainly from the and maths in 1945. He quickly found most pleasure
astronomical literature rather than from his own in organic chemistry, and after graduation he
76
Cormack, Allan Macleod

worked with J C Sheehan on synthetic variants of inseparable), moving to the USA in 1922 and sharing
penicillin. Thereafter his work was mainly in the a Nobel Prize in 1947, the only other husband and
area of structure and synthesis of organic com- wife pairs to do so being the Curies in 1903 and the
pounds, at first at MIT and from 1959 as a professor Joliot-Curies in 1935. Gerty Cori became the first
at Harvard. woman medical graduate to receive a Nobel Prize.
Organic chemists had been much concerned for a Their best-known joint research concerned the
century with devising syntheses of molecules, with conversion of glucose to glycogen in the animal
some emphasis on those occurring as natural prod- body and the reverse breakdown. Bernard had
ucts. These, and especially those showing impor- shown in 1850 that glycogen forms an energy
tant physiological properties, were often difficult reserve held in the liver and muscles, which is con-
to obtain pure and in reasonable quantity; and verted to the simpler sugar, glucose, when needed.
experience had shown that variants on them could The Coris discovered the precise steps involved in
possess useful new properties, as in the case of this essential biochemical process and revealed the
penicillin. part played by sugar phosphates for the first time.
Corey devised a new and systematic way of plan- They showed in 1936 that a key intermediate is glu-
ning syntheses, replacing the near-artistic creative cose-1-phosphate (‘Cori ester’).
route by what he called retrosynthetic analysis. He A continuing aspect of their work was the effect
defined rules whereby the target molecule, of of hormones, especially insulin, adrenalin and the
known structure, was notionally broken down into pituitary hormones, on glucose metabolism: stud-
smaller parts, and these in turn into smaller mole- ies obviously related to diabetic disease.
cular fragments, until units were reached which The Coris shared the Nobel Prize with B A Houssay
are readily available, preferably commercially. The (1887–1971), an Argentinian physiologist in Buenos
fragmentation stages were selected to be reversible Aires who showed that one of the hormones of the
by practical means. Corey showed that these plan- pituitary gland opposed the action of insulin (which
ning steps are amenable to computer program- is formed in the pancreas). Thereafter it was realized
ming. As a result, since the 1970s many valuable that the endocrine glands interact through a com-
new compounds have been made. Corey himself plex of feedback mechanisms, still only partly
made over 100 important natural products, usually understood.
Coriolis, Gaspard Gustave de [koriohlis] (1792–
having a complex structure: for example the plant
hormone gibberelic acid (in 1978), the several types 1843) French physicist: discovered the Coriolis iner-
of prostaglandin, and ginkgolid from the ginkgo tial force.
tree, long used in China to treat asthma. Coriolis was educated at the École Polytechnique
Corey won an unshared Nobel Prize for chemistry in Paris, where he became assistant professor of
in 1990. analysis and mathematics and eventually director
Cori, Carl Ferdinand [koree] (1896–1984) and Cori, of studies.
Gerty (Theresa) (1896–1957) Czech–US bio- Coriolis was responsible for defining kinetic
energy as mv2 and introducing ‘work’ as a tech-
chemists.
Cori graduated in medicine in Prague in 1920 and nical term of precise meaning in mechanics. In
in the same year married his classmate Gerty 1835 Coriolis discovered the Coriolis force, an iner-
Radnitz (1896–1957). They formed a close team until tial force which acts on rotating surfaces at right-
her death (their research collaboration had begun as angles to their direction of motion, causing the
students and their contributions are practically elements of the surface to follow a curved, rather
than straight, line of motion. Such effects are par-
ticularly important in oceanography and meteorol-
ogy (eg the Ekman effect), and account for the
Earth axis
movement of ocean currents near the Equator.
Cormack, Allan Macleod (1924–98) South African–
US physicist: pioneer of X-ray tomography.
North Pole
Cormack studied at the University of Cape Town
and then worked on the medical applications of
radioisotopes in Johannesburg before moving to
anticlockwise
rotation the USA in 1956.
In 1963, independently of Hounsfield, Cormack
developed the mathematical principles for the X-
ray imaging of ‘soft’ biological tissue, and demon-
strated its viability experimentally. Hitherto, X-rays
had only been used for obtaining ‘silhouettes’, pri-
marily of bone structure. Cormack showed that by
South Pole
effectively combining many X-ray images, taken in
different directions through the human body, it
was possible to build up a picture of a slice through
Deflections (dotted lines) from expected paths (solid
the soft tissue. This technique, known as computer-
lines) resulting from the Coriolis force. They are observed
assisted tomography (CAT) or computed tomography
in the flight of missiles and artillery shells.
77
Panel: The history of astronomy


THE HISTORY OF ASTRONOMY Sun-at-centre (heliocentric) model for the Solar System
would be simpler than the Earth-centred (geocentric)
The rising and setting of the Sun, Moon and stars scheme. His book De revolutionibus orbium
must have attracted attention early in human history, coelestium (1543, On the Revolutions of the Celestial
but astronomy can be said to have begun around Spheres) set out methods for calculating the size of
3000 BC when the Mesopotamians, Egyptians, and the system and predicting the motion of the planets.
Chinese grouped the stars into constellations. By The Copernican model was at the centre of one of the
2500 BC, stone monuments such as Stonehenge and most violent intellectual controversies the world had
the pyramids attest to our concern with astronomical known, and it took a century or two for the truth to be
matters. Astronomy provided the calendar for ancient accepted. It became clear that verification required
civilizations. The heliacal rising of the star Sirius and the accurate measurement of stellar and planetary
the passage of the Sun through the equinoxes positions, and this task fell to the Danish astronomer
defined the year of 365 days. The time between TYCHO BRAHE. He improved the accuracy by a factor of
similar lunar phases led to the month. The interval nearly 20. He also collected together a vast number of
between new, first quarter, full, and last quarter planetary positional observations, and these prepared
Moon became the week. And the fact that there are the way for the work of KEPLER, who discovered that
about 12 lunar months in a year triggered the division planets had elliptical orbits and that the Sun was at a
of night and day into 12 intervals – the hours. focus of these ellipses. He also derived a relationship
HIPPARCHUS of Rhodes accurately measured the length between the orbital size and period. These three laws
of the seasons, discovered the precession of the formed the connecting link between the geometrical
Earth’s spin axis and produced the first catalogue of makeshifts of Copernicus and the ancients and the
1080 star positions, before 100 BC. gravitational discoveries of NEWTON.
The measurement of astronomical size and dis- GALILEO GALILEI made a series of spectacular dis-
tance started with ERATOSTHENES of Cyrene, who coveries by observing the sky through the newly dis-
obtained excellent values for the radius of the spheri- covered telescope. His 1609–10 observations of the
cal Earth, and ARISTARCHUS of Samos who used eclipse four major satellites of Jupiter and the phases of
timing to measure the Earth–Moon size and distance. Venus firmly established the Copernican doctrine. His
However, Aristarchus obtained an Earth–Moon dis- measurements of the height of lunar mountains and
tance that was a mere 5% of its true value. ARISTOTLE the rotation of the Sun, as exhibited by the move-
introduced the first practical proofs that the Earth ments of the sunspots, broke the bonds of
was spherical, but he also dogmatically insisted that Aristotelian perfection. Telescopes quickly improved.
the sphere was the perfect solid shape, and the HORROCKS observed a transit of Venus across the solar
sphericity of heavenly bodies and orbits convinced disc; Johannes Hevelius (1611–87) constructed lunar
him that the heavens were a region of perfection and charts; HUYGENS discovered the true nature of
as such were unchangeable. This distinction between Saturn’s rings; and CASSINI discovered a gap in these
a perfect heaven and a corruptible Earth survived for rings and four Saturnian satellites.
nearly 2000 years. In 1687 Newton published his Principia, and at a
Mercury, Venus, Mars, Jupiter and Saturn were the stroke unified celestial and terrestrial science. His
five known planets, and the explanation of their com- gravitational force, proportional to the product of the
plicated paths amongst the fixed stars provided a masses divided by the square of the distances, not
challenging intellectual exercise. Eudoxus of Cnidus only described the fall of an apple but also the orbit
(c.408–355 BC) not only had a spherical spinning of the Moon and planets, and Kepler’s three laws.
Earth at the centre of the universe, but he also intro- Newton used gravitation theory to measure the mass
duced a mathematical scheme to explain the appar- of the Sun. He also calculated the orbit of a comet.
ent motion of the Sun, Moon, and planets. Each was HALLEY continued this cometary work; he not only
given a series of transparent crystal spheres. The axis showed that comets were periodic but also accu-
of each sphere was embedded in the next sphere out. rately predicted the 1759 return of ‘his’ comet, thus
By a judicious choice of 26 spheres with different axis confirming Newton’s breakthrough. Halley mapped
directions and spin periods, the planetary motion the southern sky and discovered that stars moved.
could be modelled. Claudius Ptolemaeus (PTOLEMY) of Over many centuries the closer stars moved against a
Alexandria revised the system using eccentric and background of the more distant ones. The first
epicyclic circles that combined two perfect spherical modern star catalogue was produced by FLAMSTEED,
motions of differing periods and amplitudes. This the first Astronomer Royal.
complicated, workable, and intellectually satisfying By his discovery of binary stars, WILLIAM HERSCHEL
system was in vogue for nearly 1400 years. showed that Newton’s laws extended throughout the
Little progress was made between AD 200 and observable universe. Herschel also discovered the
1500. COPERNICUS, a Polish monk, suggested that the planet Uranus (in 1781) and estimated the shape of


78
Panel: The history of astronomy


the Milky Way. Astrophysics dawned when This not only stressed that there are giant and dwarf
FRAUNHOFER catalogued the dark lines of the solar stars, but also acted as the basis for studies of the finite
spectrum. The scale of the universe started to be lifetime of stars and their evolution. Great strides in the
established when BESSEL measured (in 1838) the dis- study of stellar interiors were made by EDDINGTON. In
tance to the star 61 Cygni. And Newtonian gravita- 1916 he discovered that stellar energy transport was by
tion had a crowning distinction when ADAMS and radiation as opposed to convection, and that stellar
LEVERRIER used gravitational perturbation analysis to equilibrium depended on radiation pressure as well as
predict the existence and position of Neptune, which gas pressure and gravitation. His model of the interior
was discovered in 1846. of a typical star indicated that the central temperature
The foundations of astronomical spectroscopy was tens of millions of degrees. In 1924 he found that
were laid in 1859 when KIRCHHOFF correctly in- the luminosity of a star depended almost exclusively on
terpreted the process responsible for the Fraunhofer its mass. In the mid-1920s CECILIA PAYNE-GAPOSCHKIN
lines in the solar spectrum. Stellar spectra were first showed that the major constituents of stars are hydro-
classified by Pietro Angelo Secchi (1818–78), and this gen and helium. HOYLE and William Fowler (1911–95)
was greatly developed by Edward Pickering (1846– put forward a theory showing how nuclear fusion syn-
1919) at Harvard with his group of women assistants, thesized other heavier elements in the centre of stars.
notably Williamina Fleming (1857–1911), ANNIE JUMP The ever-increasing size of astronomical tele-
CANNON and ANTONIA MAURY. Variations in the stellar scopes enabled detailed spectroscopy to be applied
spectra were caused by changes in surface tempera- to fainter and fainter objects. HUBBLE not only discov-
ture. HUGGINS not only showed that the Earth, stars ered (in 1924) that extragalactic nebulae were galax-
and planets were made from the same atoms, but he ies like our own but, together with SLIPHER, measured
also used Doppler shifts to measure the movement of their radial velocities and in 1929 discovered that the
astronomical objects. LOCKYER inaugurated solar universe was expanding.
physics by measuring the spectra of solar promi- Cosmology, the study of the origin of the universe,
nences at the time of total eclipse. The work of became a popular subject, with the ‘Big Bang’ theory,
MAUNDER on the variability of solar activity and HALE first proposed by LEMAIˆTRE, vying with the
on solar magnetism continued this advance. ‘Continuous Creation’ theory put forward by BONDI,
In 1866 SCHIAPARELLI demonstrated the connection GOLD and Hoyle. The discovery in 1964 of the 3.5 K
between the comets and meteor showers, and also microwave background by PENZIAS and
noticed (in 1877) ‘canals’ on Mars. This sparked a R W WILSON strongly favoured the ‘Big Bang’.
great increase in planetary observational work under Radio astronomy started in 1937, when REBER
the guidance of people such as LOWELL. A new planet, built a 9.4 m diameter radio antenna. In 1942 HEY
Pluto, was discovered in 1930 by TOMBAUGH. (1909– ) discovered radio waves from the Sun, and
During the late 19th-c photography played a large in 1944 VAN DER HULST predicted that interstellar
role in the advancement of astronomy. Unlike the hydrogen would emit 21-cm radio waves. Unusual
eye, a film is able to ‘accumulate’ light. The first radio sources such as Cassiopeia A and Cygnus A
photograph of a star was taken in 1850. Solar promi- were found, and the detection of the 21-cm radiation
nences were photographed in 1870, a stellar spec- in 1951 by PURCELL soon enabled OORT to map the
trum in 1872, the nebula M 42 in 1880, and the Milky Galaxy using radio waves.
Way in 1889. In 1891 and 1892 the photographic dis- The launch of the space race in the late 1950s saw
covery of an asteroid and a comet was achieved. The telescopes and telescopic devices lifted above Earth’s
source of solar energy and the age of the Earth were blanketing atmosphere. The first X-ray source was
also topics of great interest in the late 19th-c. discovered in 1962, and in 1969 two men walked on
EINSTEIN’S theory of mass-energy commensurability the Moon. Infrared- and ultraviolet-detecting satel-
pointed to the energy source of the Sun and other lites have followed, and space probes have to date
stars, but astronomers had to wait until 1939 for the flown past all the major planets, revealing a host of
detailed solution put forward by BETHE. new details. Unusual stellar and galactic objects con-
In 1904 Jacobus Kapteyn (1851–1922) initiated tinue to be found. White dwarfs, neutron stars, black
important research into the motion of stars in the Milky holes, pulsars and quasars are typical examples.
Way, and the size of the Galaxy was defined by the Today, astronomers are still considering such diverse
work of SHAPLEY on the distribution of star clusters. This topics as the large scale structure of the universe, the
relied on the discovery of the period–luminosity rela- origin of galaxies and the origin of the solar system.
tionship in Cepheid variable stars by HENRIETTA LEAVITT. There is evidence that planetary systems other than
Around 1914 HERTZSPRUNG and RUSSELL modified and our own exist, but messages from extraterrestrial life
extended the classification of stellar spectra. Knowing forms have yet to be detected.
stellar distances, they were able to introduce what was
Carole Stott

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