ńňđ. 13
(âńĺăî 21)



Fr Ra 1994 1994 1999 1999 1999 1999
Francium Radium elements)
(223) 226.0254 (261) (262) (263) (262) (265) (266) (271) (272)

57 58 59 60 61 62 63 64 65 66 67 68 69 70 71
Atomic Symbol
Rn La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Holmium Erbium Thulium Ytterbium Lutetium
Element Dysprosium
Atomic weight
(222) 138.9055 140.12 140.9077 144.24 (145) 150.36 151.96 157.25 158.9254 162.50 164.9304 167.26 168.9342 173.04 174.967
(most stable 89 90 91 92 93 94 95 96 97 98 99 100 101 103
isotope of radio-
active elements Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr
Actinium Thor ium Protactinium Uranium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Lawrencium
in parentheses)
227.0278 232.0381 231.0359 238.0289 237.0482 (244) (243) (247) (247) (252) (254) (257) (258) (260)

The periodic table of the chemical elements. The horizontal rows (‘periods) and the vertical columns (‘groups’) both show progressive trends in chemical and physical properties of the

Periodic table of the chemical elements

elements, reflecting progressive change in the structure of the atoms. Hydrogen, with its uniquely simple atom, appears in both groups 1 and 7.
Mercator, Gerardus

properties were found to be in good accord with
prediction. Later still, the noble gases and the
transuranium elements were fitted into the table.
The whole scheme brought order into chemistry by
allowing a great range of known facts to be
arranged and classified. It stands like Newton’s
work in physics or Darwin’s in biology as one of the
great intellectual advances in science. It was
devised on an entirely empirical basis and it was
half a century later that Moseley’s work, and that
of Bohr, provided an explanation for it in terms of
atomic structure. Mendelayev produced his table
when he was 34. It made him famous, and he
worked on it for a few years, but then moved to a
variety of other matters. It has framed and shaped
ideas in inorganic chemistry ever since. In 1955 a
new element, atomic number 101, was named
mendelevium (Md) in his honour.
Mercator, Gerardus (Lat), Gerhard Kremer (Dutch)
[merkayter] (1512–94) Dutch cartographer and geo-
grapher: invented Mercator map projection.
Educated at the University of Louvain under G
D I Mendelayev Frisius (1508–55), Mercator set up a centre for the
study of geography at Louvain in 1534, issuing a
with Bunsen in Germany. Back in St Petersburg number of maps and also making surveying instru-
from 1861, he began his career as a teacher and ments and globes. Persecuted as a Protestant, he
researcher in the university. moved to Duisberg in 1552, from where in 1569 he
His career was not smooth; he was irascible and issued a map of the world in the new projection
outspoken, supported the students’ political ideas which now bears his name. The Mercator projec-
and quarrelled with two successive ministers of tion was a great advance because it allowed naviga-
education. He and his wife divorced and he remar- tors to plot their course as a straight line of
ried, without waiting the 7 years then required by constant heading, corresponding to a great circle
Russian law. Officially a bigamist, he was not on the globe. To achieve this meridians of longitude
directly penalized for this, but the priest was; were made parallel, instead of converging at the
Mendelayev, forced out of the university in 1890, Poles. This rectangular orthomorphic projection is
became director of the Board for Weights and clearly convenient for navigators, both in allowing
Measures in 1893. Mendelayev was more honoured compass bearings to be drawn as straight lines and
outside Russia than within it, and he was never in making dead reckoning easy. Surprisingly, since
admitted to the Imperial Academy of Sciences, Mercator’s projection distorts reality so greatly, it
despite his work for the Russian chemical industry has dominated maps made for all purposes, ever
and his great scheme which brought order and pre- since his maps appeared in the late 16th-c.
diction to inorganic chemistry; this was his peri- Mercator or his sons, also mapmakers, are also
odic table (or periodic law or classification). credited with coining the term ‘atlas’ to describe a
Mendelayev saw the need for a new textbook of set of maps.
Meselson, Matthew (Stanley) (1930– ) US mol-
chemistry in the 1860s, and in shaping his ideas for
this book he prepared a series of cards, each listing ecular biologist: showed how the DNA double helix
the main properties of one chemical element; he replicates.
liked playing patience as a relaxation. In arranging Born in Colorado, Meselson first studied liberal
these, he was struck by the fact that if the 60 cards arts at Chicago and then physical chemistry at
were placed in rows of suitably varying length, with Caltech, where he remained to teach physical
most of the elements in order of increasing relative chemistry. In 1961 he moved to Harvard.
atomic mass, then elements with similar chemical When Crick and Watson in 1953 proposed that
features were found to lie in the vertical groups (the genes were constructed of a double helix of DNA,
periodic law). Mendelayev did not know of New- they also suggested that, when this duplicated,
lands’s primitive work on similar lines, and his each new double helix in the daughter cells would
went much further. In his table of 1868–9, he boldly contain just one DNA strand from the original helix
transposed some pairs of elements on the basis that (‘semiconservative replication’). The alternative
their claimed atomic masses must be in error if would be for one daughter cell to contain both the
they were to fit the scheme; likewise he left spaces old strands and the other daughter to receive both
for three yet undiscovered elements. He predicted new strands (‘conservative replication’). In 1957
the properties of the latter from those of their Meselson and F W Stahl (1929– ) showed by inge-
known neighbours. By 1886 the predicted elements nious experiments using the bacterium Escherichia
were discovered by other chemists, and their real coli labelled with nitrogen-15 that replication is
Panel: The history of genetics

THE HISTORY OF GENETICS bacterial transformation was reported in 1928, but
the nature of the transforming agent was only
Although appreciation of inheritance as a determi- revealed as deoxyribonucleic acid (DNA) by the work
nant of the characteristics of living species probably of AVERY and colleagues in 1944. In 1952 HERSHEY and
began with the introduction of agriculture several Martha Chase (1927– )confirmed these findings
millennia ago, the scientific study of genetics is and firmly established DNA as the chemical material
largely a 20th-c phenomenon. It has developed along of the gene.
a number of independent but occasionally over- A curious feature of the history of genetics is that
lapping avenues. These include breeding studies on an early clue to the function of the genes was pro-
whole organisms (and observations of the effects of vided by the work of GARROD within a year of the
breeding in humans), microscopic examination of rediscovery of Mendelian principles in 1900. He
cells and chromosomes, chemical investigation of the studied a rare human disease called alkaptonuria,
material of genes and the biochemical pursuit of which behaved as though inherited as a recessive
gene action. trait. Affected children excrete large amounts of
The first real scientific studies of hereditary factors homogentisic acid in their urine, and Garrod specu-
controlling the phenotype of a species began with the lated that this resulted from the absence of a specific
work of the Austrian monk MENDEL, published in enzyme. But although the relationship between gene
1866. Choosing the garden pea for his breeding and enzyme was implicit in his work, it was an idea
experiments, he showed that (1) his plants inherited before its time. Some 40 years later, BEADLE and
two factors for each trait he studied, with one derived Edward Tatum (1909–75) reformulated this concept
from each parent; (2) inherited factors did not blend in a precise form, ‘one gene, one enzyme’ – subse-
or mix in the offspring, but were segregated; (3) some quently modified to ‘one gene, one polypeptide
factors were dominant over others; and (4) factors chain’. In 1949, SANGER devised a method for deter-
controlling different traits in the plants assorted inde- mining the amino-acid sequence of protein mole-
pendently. He also suggested that it was the germ cules. It is now accepted that the primary function of
cells that were responsible for the transmission of the genes is to carry the information that specifies the
inherited factors. chemical nature and quantity of unique proteins.
Mendel’s experiments lay largely unnoticed until By the early 1950s the conceptual framework was
1900. During the intervening years, the cell theory in place to launch a more fundamental attack on the
was developed, and it was proposed that the physical structure and function of the hereditary material. The
basis of inheritance lay in the cell nucleus, and in all era of molecular genetics began in 1953, when CRICK
probability in microscopically visible particles called and WATSON proposed a two-stranded model for
chromosomes. WEISMANN formulated the idea of the DNA, with complementary chains wound around
continuity of the germ plasm, and suggested that each other in a double helix. An early clue to this
there must be a reduction in the number of chromo- structure came from the work of CHARGAFF, who had
somes in the germ cells to one half of that in the body separated and measured the four nucleic acid bases –
cells in sexually reproducing organisms. However, it thymine (T), cytosine (C), adenine (A), and guanine
was not until 1903 that Walter Sutton (1877–1916) (G) – in DNA from several species, and found that the
and BOVERI drew attention to the parallels between amount of A equalled that of T, while the amount of
Mendel’s segregating factors and the behaviour of G equalled that of C. On the basis of X-ray crystallo-
chromosomes in meiosis. Inherited factors were graphic studies by Maurice Wilkins (1916– ) and
named genes by W L Johanssen (1857–1927) in 1909. ROSALIND FRANKLIN, Crick and Watson were able to
In the following years, MORGAN showed that genes build an accurate model of DNA, with the As in one
lying close together on chromosomes could be inher- chain hydrogen-bonded to the Ts in the other, and Cs
ited together in linkage groups, which occasionally in one chain bonded to the Gs in the other. Inspection
broke apart in a process called crossing-over or of this self-complementary model suggested a mech-
recombination. In 1931, BARBARA MCCLINTOCK corre- anism for the exact replication of these genes in each
lated the microscopically visible rearrangements of cell generation, with the helix unwinding and old
chromosome segments with the redistribution of strands forming the templates for newly synthesized
specific genetic traits in maize. By the mid-1930s it daughter strands. This semi-conservative nature of
was accepted that genes had physical reality and DNA replication was demonstrated experimentally by
were determinants of biological specificity. MESELSON and Franklin Stahl (1929– ) in 1958.
The chemical nature of genes emerged more Because the Watson–Crick model placed no
slowly. Although Friedrich Miescher (1844–95) had restriction on the sequence of bases in a single strand
described nucleic acid in 1869, cell nuclei also of DNA molecule, it provided a satisfactory explanation
contain abundant protein. The phenomenon of for its role as carrier of the hereditary information.

Meyer, Viktor

Working out how base sequences were turned into of genetics, but also on the pharmaceutical, agricul-
the amino-acid sequences of specific proteins occu- tural and food industries. It has also begun to provide
pied most of the next decade. It became apparent a route to the understanding and prevention of
that DNA was transcribed first into messenger human diseases. In the past decade, a large number
ribonucleic acid (RNA) and only then translated into of human genes have been identified, many of whose
protein. RNA and DNA sequences were complemen- mutant forms are responsible for the types of
tary. The genetic code was cracked by the elegant Mendelian disorder first described by GARROD, and
experiments of Marshall Nirenberg (1927– ) in the later catalogued and indexed by V A McKusick
USA, and Severo Ochoa (1905–93) and colleagues in (1921– ). Some of these will be treated successfully
Spain. Nirenberg showed conclusively that it was a by gene therapy – the introduction of normal genes
triplet code, with a sequence of three bases deter- into affected tissues and organs. The discovery of
mining each individual amino acid. By 1969, 100 oncogenes and tumour-suppressor genes, both
years after the first description of DNA by Miescher, mutant forms of normal cellular genes, is in the
the details of the genetic code were complete. process of revolutionizing the understanding of
It was now possible to approach the study of cancer. Even in the common multifactorial diseases,
genetics through the gene itself. However, DNA is a with mixed environmental and genetic origins, the
large molecule of relative chemical homogeneity and application of molecular techniques has begun to
could not be cleaved in a reproducible manner. This lead to the identification of major susceptibility
problem was solved with the discovery of restriction genes.
endonucleases by Werner Arber (1929– ), HAMILTON Although methods for determining the order of
SMITH, and Daniel Nathans (1928– ). These the bases in DNA fragments were reported only in
enzymes cut double-stranded DNA at recognition 1977, so rapid was the progress of molecular genet-
sites determined by particular base sequences, and ics that by 1985 it was possible to contemplate
sequencing the entire human genome (3 x 109 base
thus allowed the genes to be digested into consistent
segments, a process known as physical mapping. pairs). This idea, termed the Human Genome Project
Furthermore, the DNA segments were now small (see panel, p. 368), was initially controversial and
enough to be cloned into plasmid vectors and then some feared that the megascience involved would
amplified to a high copy number by growing in bacte- siphon funds away from other branches of biology.
rial hosts, thus ushering in the era of recombinant However, progress was so rapid that by June 2000 a
DNA technology. Another contribution to the new first working draft covering most of the human
science was made by Ed Southern (1933– ), who genome was published. Early completion of the
showed that DNA fragments could be bound to nitro- sequence means that genetics has moved from
cellulose filters and identified by hybridization to Mendelian rediscovery of the principles of inheritance
complementary sequences. In 1977, Sanger, WALTER to a complete molecular blueprint of the genome in
GILBERT and their colleagues independently described the space of 100 years.
two different and equally reliable methods for deter-
mining the base sequences of DNA molecules.
Professor David Brock, Human Genetics Unit,
The ability to clone and manipulate selected genes
University of Edinburgh
has had a profound influence not only on the science

indeed semiconservative; an important result, veri- duly converted him. He became an enthusiastic and
fying Crick and Watson’s ideas and using intact successful chemistry student, and later a strikingly
dividing cells without the use of injurious agents. effective lecturer, perhaps because of his acting
Meselson also worked on ribosomes, the cell orga- skills. After working as assistant to Bunsen and to
nelles that are the site of protein synthesis. The Baeyer he became professor at ZĂĽrich at the early
ribosomes are ‘instructed’ on protein construction age of 24. Later he succeeded Bunsen at Heidelberg,
by m-RNA and if given abnormal instructions will but in the 1880s he became ill and depressed and
produce abnormal protein. When a virus invades a later killed himself with cyanide, a fate too
bacterial cell, the viral DNA releases its m-RNA, common among famous chemists.
which acts on the bacterial ribosomes, causing His early work on benzene compounds estab-
them to make viral protein rather than bacterial lished the orientation of many substituted acids,
protein. but his main fame in the 1870s was due to his work
Meyer, Viktor [miyer] (1848–97) German chemist: on nitroparaffins; he was also the first to prepare
wide-ranging chemical experimenter. oximes, by the reaction of hydroxylamine H2NOH
Meyer’s father, a dye merchant, wished his sons with an aldehyde or ketone. His name is much
to become chemists; Viktor wanted to be an actor. linked with a method for finding relative molecu-
The family persuaded him to attend some lectures lar mass by measuring vapour density; he used this
in Heidelberg, and Bunsen’s lectures on chemistry first for organic compounds and then (at tempera-
Michelson, Albert Abraham

tures up to 3000°C) for inorganic compounds and of explaining the large number of apparent close
elements. In 1883 he discovered (through a lecture pairs that had been observed, which he argued
demonstration which failed) the novel sulphur could not be due merely to the chance of the two
ring-compound thiophene, parent of a series of sul- stars being near the same line of sight. In 1803 F W
phur compounds. He also did valuable work in Herschel found observational proof for his proposal.
stereochemistry (he invented this word, usefully In a particularly far-sighted suggestion, Michell
shorter than van ’t Hoff’s ‘chemistry in space’) and proposed in 1783 that if stars were sufficiently mas-
he discovered ‘steric hindrance’, which he first sive and compact then light would not be able to
observed in ortho-substituted benzoic acids. He escape from their surface; such objects are today
made a novel range of aromatic iodine compounds known as black holes. He thought that there might
and he studied what later came to be seen as elec- be a large number of black holes, and further sug-
tronic effects on acidity in organic molecules. gested that they might be detectable through their
Meyerhof, Otto Fritz (1884–1951) German–US bio- gravitational effect on nearby objects.
chemist: elucidated mechanism of lactic acid for- Michell was also the first to make a realistic esti-
mation in muscle tissue. mate of a stellar distance, using a neat argument
Meyerhof studied medicine at Heidelberg and based on apparent brightness. He deduced a distance
began to specialize in psychiatry. However, he of 460 000 AU for the star Vega, about a quarter of
became attracted to biochemistry and in 1909 today’s value.
Michelson, Albert Abraham [mikelsn] (1852–
worked with Warburg and studied his methods;
afterwards in Kiel, Berlin and Heidelberg, he used 1931) US physicist: devised optical measurement
similar techniques to examine the chemical changes methods of great accuracy; and showed that the
linked with muscular action. F G Hopkins had hypothetical ether probably did not exist.
shown that lactic acid is formed in a working Born in Strelno (now in Poland), Michelson emi-
muscle, and Meyerhof showed how this is formed grated with his parents to the USA as a child of 4. At
and how it is removed when the muscle rests. He 17 he entered the Annapolis Naval Academy (after
became increasingly unhappy in Nazi Germany, an entry appeal in which he saw President Grant)
moved to France in 1938 and when France fell in and, following graduation and a tour of duty at sea,
1940 escaped to the USA and worked in was appointed as instructor in physics and chemistry
Philadelphia until his death. He shared a Nobel there.
Prize in 1922 with A V Hill (1886–1977), who had His interest in science was apparently much
worked in Cambridge and Manchester on the heat increased from this time and, when he needed to
evolved in muscle action. Hill was able to demonstrate to the midshipmen how the speed of
measure this with delicate thermocouples and to light can be measured, he applied himself to
deduce from his results that oxygen is taken up improving the accuracy of the measurement. It is
only after (and not during) the action of muscle. certainly of fundamental importance for physics
Michaelis, Leonor [meekaylis] (1875–1949) (and for navigation) and Michelson was to measure
German–US biochemist: made early deductions on it with increasing accuracy throughout his life. The
enzyme action. optical devices he used for this, based on his inter-
Educated in Germany, Michaelis worked in Berlin ferometer, were useful for a variety of purposes in
until 1922 when he went to Japan; in 1926 he physics.
moved to the USA, first to Johns Hopkins and then In the early 1880s he visited Europe for 2 years on
to the Rockefeller Institute. He showed in 1913 that study leave, and his first interferometer was built
an expression (the Michaelis–Menten equation) in Helmholtz’s laboratory and paid for by A G Bell.
will describe the change in the rate of an enzyme- It allowed the speed of light to be compared in two
catalysed reaction when the concentration of sub- pencils of light split from a single beam. One result
strate is changed; and from this and other studies of this work concerned the so-called ether. Since
he deduced that reaction between an enzyme and waves such as sound waves or water waves require
its substrate was preceded by their combination to a substance or ‘medium’ for their transmission, it
form a complex. It was 50 years before this was con- had been widely presumed that light and other
firmed by direct experiments; rate studies on electromagnetic waves must likewise require a
enzymes and on the transport of substances medium, and a hypothetical ether, invisible, uni-
through cell membranes are now normally based versal and weightless, had been invented for the
on these ideas. purpose. However, Michelson’s refined results
Michell, John (c.1724–93) British astronomer: dis- would show the effect on light of the Earth’s
covered double stars, estimated stellar distances motion through the ether; but there was no effect
and predicted existence of black holes. and physicists were forced to doubt if the ether
A Cambridge graduate in divinity, Michell was really existed.
professor of geology there for 2 years before becom- In 1881 Michelson left the Navy, and next year
ing a village rector near Leeds, a post he held for became professor of physics in Cleveland, OH.
life. There he continued and improved his optical
His scientific work was mainly in astronomy, measurements, and with Morley (the professor of
where he made several significant contributions. chemistry) confirmed the null result on the ether in
He proposed the existence of double stars as a way 1887. This classical Michelson–Morley experiment,
Midgley, Thomas

a major result in physics, won him a national prize in Milankovich was educated in Vienna, but in 1904
1888, ‘not only for what he has established, but also moved to the University of Belgrade, where he spent
for what he has unsettled’. In a sense the problem was the rest of his academic career. He is remembered
not ‘settled’ until 1905 when Einstein’s theory of for his work on the cause for long-term changes in
relativity dispensed with the need for ether. the Earth’s climate. Following earlier proposals by J
Michelson went on to apply his ingenuity and Herschel and J Croll (1821–90), he recognized that
skill in optics to measure the metre in terms of the the major influence on the Earth’s climate is the
wavelength of light and to solve some astronomical amount of heat received from the Sun. Three astro-
problems (he was the first to measure the angular nomical factors can affect this: the eccentricity of
diameter of a star; it was Betelgeuse, and the the Earth’s orbit (which varies on a time scale of
margin of error was equivalent to a pinhead’s about 100 000 years), the tilt of the Earth’s axis
width at a distance of 1000 miles) and to refine his (time scale of 40 000 years), and a precessional
value for the velocity of light (close to 3 × 108 m s –1 change which determines whether the northern or
in air). He also discovered new features of spectra; southern hemisphere receives most radiation (time
and he used his interferometer to measure tidal scale of 20 000 years). Milankovich spent 30 years
movement due to the Moon’s effect not on the seas, computing the amount of radiation received at dif-
but on the solid Earth. From 1890 until his death he ferent latitudes for the past 650 000 years, and was
worked at Chicago; in 1907 he became the first able to demonstrate that changes in insolation cor-
American awarded a Nobel Prize. (Portrait on p. 106) responded with the then known ice ages. Since
Midgley, Thomas (1889–1944) US engineer and Milankovich’s work in the 1920s, the number of
inventor: introduced tetra-ethyl lead (TEL) anti- known ice ages has increased, and their history is
knock and Freon refrigerant. seen as complex. Although the Earth’s orbital varia-
Midgley was the son of one inventor and the tions are important, it is now clear that as well as
nephew of another. He studied engineering at the cooler summers studied by Milankovich and
Cornell, finishing with a PhD in 1911. Working with ascribed by him to these orbital variations, other
C Kettering for Delco in the First World War, he led factors probably contributed to ice age formation.
a team working on the problem of ‘knocking’ in One such is the level of CO2 in the atmosphere;
petrol engines. (‘Knocking’ or ‘pinking’ is the metal- Tyndall and Arrhenius both studied the way in
lic noise caused by pre-ignition.) After finding some which loss of CO2 and therefore of its ‘greenhouse
anti-knock additives as a result of random trials, effect’ could cool the Earth, and interest in this rose
Midgley realized that their effectiveness could be in the 1970s after study of air bubbles trapped in
related to the position of the heaviest atom in the polar ice cores gave information on CO2 levels over
compound, within the periodic table. On this basis, a long period. Certainly over the last million years
working at General Motors in 1921, he tried tetra- the oceans have varied in temperature and volume,
with the global ice mass changing by some 1019 kg
ethyl lead, Pb(C2H5)4, and found it to be very effec-
tive, used with some 1,2-dibromo-ethane to reduce and resulting in changes in sea level of up to 100 m.
lead oxide deposits in the engine. The mixture was Over the same period, CO2 has varied by up to 30%.
widely used, but rising concern from 1980 that lead A complete theory of factors leading to ice ages
in vehicle exhausts was a health hazard for children must be complex, and good models are not yet
caused it to be phased out in the 1990s. Midgley also available.
Miller, Jacques (Francis Albert Pierre) (1931– )
devised the octane number method of rating petrol
quality. French–Australian immunologist: discovered func-
In 1930 Midgley introduced Freon-12 (CF2Cl2) as a tion of the thymus gland.
non-toxic non-flammable agent for domestic refrig- Educated in Sydney and London, Miller worked
erators; again, he used the periodic table as a guide from 1966 at the Hall Institute, Melbourne. Until
to select a suitable compound with the required his work in 1961, the function of the thymus gland
properties. From the 1980s there was concern that was not known. The gland is in the chest of mam-
chlorofluorocarbons (CFCs) such as Freon cause mals, close to the heart, and becomes relatively
destruction of the ozone layer of the upper atmos- smaller from infancy to adulthood. To discover the
phere, with potentially damaging climatic and function of such an organ, one general method is to
other effects as a result of the increased passage of remove it from a mature experimental animal and
ultraviolet radiation following ozone loss. Political to examine the resulting changes; but in the case
will to deal with this has been sluggish, and the of the thymus, no significant change could be
‘ozone hole’ over the south polar region, and its observed. Likewise its removal in human adults in
effects, are worsening. cases where it had become cancerous produced no
For one man to invent two major environmental obvious physiological change. Miller pointed to an
hazards is curious; and so was his death. A polio answer by removing the thymus from 1-day-old
victim, he had devised a harness to help him rise in mice (which weigh only about a gram). Then,
the morning. Becoming in some way entangled in thymectomy produced much change; normal
it, he strangled himself. growth failed and death followed in 8–12 weeks.
Milankovich, Milutin (1879–1958) Serbian clima- Suggestively, the lymph nodes shrink, the lympho-
tologist: developed astronomical theory of climatic cyte blood count falls and immune responses fail,
change. so that skin grafts from unrelated mice (or even
Milstein, CĂ©sar

rats) are not rejected. From this basis, later work always occurred in multiples of a single value, the
showed that T-lymphocytes are formed in the fetal charge (e) on a single electron. Millikan was lucky to
use a field strength (about 6000 V cm –1) within the
thymus and fulfil a critical role in the complex cell-
mediated immune response. narrow range in which the experiment is possible.
Miller, Stanley Lloyd (1930– ) US chemist: exper- He then studied the photoelectric effect (1912–
imented to simulate production of pre-biotic bio- 16) confirming Einstein’s deduction of 1905 that
chemicals from simple gas mixtures. the energy E of an electron emitted from a metal by
A graduate of California and Chicago, Miller light is given by E = hv – Eo where v is the frequency
worked at the University of California at San Diego of the incident radiation, Eo is the energy required
from 1960. His most familiar work was done when to leave the metal (the work function) and h is
he was a research student with Urey in Chicago in Planck’s constant. For his accurate measurements
1953. Interested in the possible origin of life on of e and h Millikan was awarded the 1923 Nobel
Earth, he devised an experiment using an early Prize for physics.
planetary reducing atmosphere as proposed by During the 1920s Millikan researched on cosmic
Urey in 1952; it contained water vapour, methane, rays, showing in 1925 that they come from space.
ammonia and hydrogen. This simple gas mixture Millikan argued that they are uncharged and consist
(H2O, CH4, NH3, H2) was passed for some days of electromagnetic radiation, but Compton showed
through an electric spark discharge (to simulate a them to consist of particles. However, Millikan was
thunderstorm’s energy input) and Miller then responsible for directing C D Anderson to view
analysed it. He found traces of hydrogen cyanide, cosmic rays in a Wilson cloud chamber, which led to
methanal, methanoic, ethanoic and other acids, Anderson’s discovery of the positron. (Portrait on p. 106)
Milne, Edward Arthur (1896–1950) British astro-
urea and a mixture of amino acids. The result is cer-
tainly suggestive, bearing in mind the short period physicist and mathematician: proposed the cosmo-
of the experiment in comparison with ‘prebiotic logical principle.
time’. Since Miller’s work, others using similar Milne was educated at Cambridge, where he later
methods and other intense energy sources (eg ultra- became assistant director of the Solar Physics
violet light and gamma radiation) have produced Observatory. In 1929 he was appointed professor of
more complex organic molecules (including the mathematics at Oxford, and stayed there for life,
nucleic acid base, adenine) but it remains very except during the Second World War, when he
unclear how a mixture of organic compounds worked on ballistics, rockets and sound ranging for
might have evolved into something like a living the Ordnance Board.
system as we now know it. Milne’s early work was on stellar atmospheres, in
Millikan, Robert Andrews (1868–1953) US physi- particular the relationship between stellar class and
cist: determined e and h accurately for the first time. temperature. In 1932 he turned to cosmology,
Millikan was the son of a Congregational minis- proposing the cosmological principle – that the uni-
ter and small farmer and grew up in the still roman- verse appears (on the macroscopic scale) the same
tic age of the American midwest. His talent at from whatever point it is viewed. This remains a
school was mainly in classics, and he did little basic axiom of much modern cosmological thought.
physics; but in his second year at Oberlin college he Milne later attempted to deduce a complete model
was invited to teach elementary physics and was of the universe from somewhat philosophical ‘first
told ‘anyone who can do well in Greek can teach principles’, but was not successful.
Milstein, César (1927–2002) [milstiyn] Argentinian–
physics’. He learned quickly and was soon
immersed in the subject, which was not then much British molecular biologist: co-discoverer of mono-
developed in the USA. Then he went to Columbia, clonal antibodies.
where he was the sole graduate student in physics
there in 1893–5, working at the US Mint on the
polarization of light emitted from the incandescent
surface of fused gold and silver. Later he studied in
Germany, and in 1896 was offered a job in Chicago
with Michelson. He took it, and was there until he
went to the California Institute of Technology in
Between 1909 and 1913 Millikan determined the
charge on an electron with considerable accuracy,
not surpassed until 1928. Between two horizontal
plates a cloud of fine oil droplets was introduced
and irradiated with X-rays so as to introduce vary-
ing amounts of charge on some of them. By adjust-
ing the voltage on the plates, electric force and
buoyancy could be made to just counterbalance
gravity for an oil-drop viewed by a microscope.
Calculation then revealed its charge; a long series
of measurements showed that the measured charge CĂ©sar Milstein
Minkowski, Rudolph Leo

Born and educated in Argentina, Milstein was a MA, one of 10 children of a schoolteacher and ama-
chemistry student, research student and staff teur astronomer. Her education in private elemen-
member in Buenos Aires before his first stay in tary schools finished when she was 16. However,
Cambridge from 1958. Back in Buenos Aires in Nantucket was an area where it was usual to
1961, he returned to Cambridge in 1963 to join become familiar with some mathematics, astron-
Sanger on the Medical Research Council staff. omy and navigation. Mitchell assisted her father
There he worked on the structure of an immuno- with his astronomical observations and learned to
globulin (an antibody) and then on a corresponding use his instruments. In 1836 she was appointed
m-RNA, which led him towards monoclonal anti- librarian at the Nantucket Atheneum and contin-
bodies (MCAs). An MCA is a single, specific and ued with her studies and astronomy. In 1847 she
chemically pure antibody produced in cloned cells, observed a new comet and won a gold medal which
ie cells that are genetically identical, by a method had been offered by the king of Denmark for such a
devised in 1975 by Milstein and G Köhler (1946–95). discovery, despite competition from observers in
Such MCAs are of great value in diagnosis and test- Rome and Britain. From this time she was hon-
ing – for example they are now routinely used in oured as a leading astronomer. In 1849 she became
the UK for typing of blood before transfusion – and a computor for the American Ephemeris and Nautical
they are potentially valuable in therapy, eg an MCA Almanac and began to work for the United States
against Rhesus-D antigen (anti-D) can now be used Coast Survey. She visited observatories in England
for mothers who are Rh-negative and have just and Europe, and met many of the scientists of the
given birth to Rh-positive children. time. In 1865 she became professor of astronomy
To make an MCA, formation of the required anti- and director of the observatory at Vassar College,
body is first induced in an experimental animal by New York.
Mitchell, Peter (Dennis) (1920–92) British bio-
injection of an antigen. After a few weeks, antibody-
rich B-lymphocytes are taken from its spleen. These chemist: devised new theory of cellular energy
cells are then fused with a malignant cell line (such transport.
as a myeloma cell). In some cases the resulting cell, It is rare for a scientist of this generation to
a hybridoma, combines the lymphocyte’s ability to create, direct and equip his own laboratory and
produce a pure antibody with the cancerous cell’s institute; it is also unusual to develop a theory
immortality, so that after selection and cloning it which first attracts widespread opposition but later
can be grown in culture indefinitely in laboratory achieves full acceptance. Mitchell did both.
conditions; in this way the antibody (which is nor- Educated in Cambridge, he went on to teach bio-
mally present in serum only in trace amounts and chemistry there and in Edinburgh before taking
mixed with other antibodies) can be produced in over the ruined Glynn House near Bodmin in
quantity. Cornwall in 1963. This he restored, partly with his
The discovery of MCAs promises a revolution in own skills, and converted it into his family quarters
biological research and in clinical diagnosis, and and a research laboratory. There he developed his
possibly in treatment for a variety of diseases, chemiosmotic theory of energy generation in the
including some cancers. Milstein, Köhler and N mitochondria and chloroplasts of plant cells, using
Jerne (1911–94) shared a Nobel Prize in 1984. Jerne, a novel concept of protonic coupling. Working par-
an immunological theorist, had proposed in 1955 ticularly with Jennifer Moyle, his valued techni-
the first selection theory of antibody formation, cian, his experimental work supported and
which was then expanded by Burnet, who pro- expanded his theory in detail. After a decade this
posed the clonal selection theory. This states that convinced his peers and led to his Nobel Prize for
each antibody is produced by a lymphocyte and chemistry in 1978.
Mitscherlich, Eilhardt [mitsherleekh] (1794–1863)
that the effect of antigen is just to increase the
number of cells producing specific antibodies. German chemist and mineralogist: discovered law
Later G Nossal (1931– ) showed that, as predicted, of isomorphism.
individual lymphocytes produce only one kind of Mitscherlich’s youthful enthusiasm was the
antibody, a necessary result for success in produc- Persian language, which he studied at Heidelberg
ing useful hybridomas. and Paris in the hope of visiting Persia as a diplo-
Minkowski, Rudolph Leo [mingkofskee] (1895– mat. When this appeared impossible he decided to
1976) German–US astronomer: made first optical study medicine, with the intention of travelling as
identification of a radio galaxy. a physician. To begin, he studied science in
In 1954 Minkowski, with Baade, made the first Göttingen; and was soon so attracted by chemistry
definite optical identification of a radio source that he gave up the idea of visiting Persia. He moved
beyond our Galaxy, Cygnus A. This object was found to Berlin in 1818 to study chemistry and soon
to be a very distant galaxy emitting an immense noticed that potassium phosphate and potassium
amount of radio energy, about 10 million times arsenate form nearly identical crystals. He went to
that generated by a normal galaxy, and it is thought Stockholm to work with Berzelius for 2 years, con-
to be undergoing a violent explosion. tinuing to measure crystal angles and forms; where
Mitchell, Maria (1818–89) US early female these were closely similar in different compounds,
astronomer; observed a new comet. he described them as ‘isomorphous’. His law of iso-
Maria Mitchell was born on Nantucket Island, morphism states that isomorphous crystals have
Moissan, Henri

similar chemical formulas. For example, he showed types, with one of each pair having, he decided,
that the manganates, chromates, sulphates and travelled through deeper and denser rocks and
selenates are isomorphous; from this the formula arrived before waves travelling through the Earth’s
of the newly discovered selenates could be deduced crust. He realized that the Earth’s crust must there-
(as the formulas of the first three were known) and fore overlay a denser mantle, and measured the
from the formula the relative atomic mass of depth to this transition (the Mohorovi˘i´ disconti-
selenium was found by analysis. From 1825 nuity, or ‘Moho’) to be about 30 km. This corre-
Mitscherlich was professor of chemistry at Berlin. sponds to the thickness of the continental crust.
Berzelius and others found the law useful in The depth of the Moho has now been extensively
deducing formulas, and therefore relative atomic mapped using reflection seismic techniques and is
masses, for several elements and for correcting ear- known to vary between only 10 km under the
lier erroneous formulas. Mitscherlich continued oceans and about 50 km at some places beneath the
his work on crystallography; he found that some continents.
Mohs, Friedrich [mohz] (1773–1839) German–
substances (eg S) can crystallize in two forms
(dimorphism) or even more (polymorphism). From Austrian mineralogist: devised a scale of mineral
1825 Mitscherlich was professor in Berlin. As well hardness.
as crystallography, he worked on organic chem- Born appropriately at Gernrode in the Hartz
istry, microbiology, geology and catalysis. He first mountains (which are rich in minerals), Mohs
made benzene (and named it Benzin) by heating became professor of mineralogy at Graz in 1812
calcium benzoate; and also nitrobenzene, azoben- and at Vienna in 1826. He is now remembered for
zene and benzenesulphonic acid. He helped his the scale of relative hardness named after him. This
youngest son develop an important industrial runs from talc (1) to diamond (10); the mineral with
process for obtaining cellulose from wood pulp by the higher number scratches anything beneath it
treatment with hot aqueous calcium hydrogen sul- or equal to it in hardness. The scale is not linear (the
phite solution. true hardness differences do not coincide with the
Möbius, August Ferdinand [moebyus] (1790– simple intervals of Mohs’s scale); and the hardness
1868) German mathematician and astronomer: of crystals is usually different in different crystal
inventor of barycentric calculus and of the Möbius directions. The scale is useful in field mineralogy.
Moissan, (Ferdinand Frederic) Henri [mwasĂŁ]
Möbius studied law at the University of Leipzig, (1852–1907) French inorganic chemist: first isolated
before abandoning it in favour of mathematics and fluorine; pioneer of high-temperature chemistry.
astronomy. In 1816 he was appointed professor of Coming from a poor family, Moissan’s pursuit of
astronomy at Leipzig, and in 1848 became director education and his enthusiasm for chemistry
of its observatory. proved difficult until marriage and a generous
Although in mathematics Möbius developed father-in-law eased his financial position. After his
barycentric calculus, which simplifies a number of first successes in chemistry, he held posts in Paris at
geometric and mechanical problems, he is better the university. In the early 1880s he began to exper-
known for his work on topology. In this field he iment on ways to isolate the element fluorine from
invented, to illustrate the idea of a one-sided sur- its compounds. Earlier attempts by Davy and others
face, the Möbius strip. This can be formed by taking had shown only that fluorine must be highly reac-
a strip of paper, rotating one end through 180° and tive, and some attempts had fatal results. Moissan
connecting the ends together. Möbius’s description succeeded in 1886 by electrolysis of a solution of KF
of it was only discovered in his papers after his in HF, at –50° in an apparatus made of platinum
death. Möbius is also remembered for posing the and calcium fluoride. Fluorine was isolated at the
‘four-colour problem’ in a lecture in 1840: what is anode as a yellow gas, and, as the most chemically
the least number of colours needed in a plane map reactive of all elements, afforded Moissan a rich
to distinguish political regions, given that each seam of new chemistry.
boundary must separate two differently-coloured Later he explored boron chemistry (he was the
regions? No such map requiring five colours has first to make pure boron) and he attempted the syn-
been found, despite attempts, and in 1976 a com- thesis of diamond by crystallizing carbon from
puter-based proof was offered showing that four molten iron under pressure. He was the first to
colours will always suffice. make a range of metal hydrides, which proved to be
Mohorovici´ ,˘c Andrija [mohhorohvuhchich] highly reactive. His interest in high-temperature
(1857–1936) Croatian geophysicist: discovered the chemistry led him to devise electric furnaces in
boundary between the Earth’s crust and the which a carbon arc gave temperatures up to
mantle. 3500°C. In this way another new area of chemistry
A talented young man who spoke eight languages was opened up and Moissan was able to make syn-
when he was 15 years of age, Mohorovi˘i´ was edu-
cc thetic gems such as ruby, and silicides, borides and
cated at the University of Prague, being appointed carbides of metals, as well as metals such as Mb, Ta,
professor at the Zagreb Technical School in 1891, Nb, V, Ti, W and U which were then little known. He
and later at Zagreb University. In 1909, while study- was awarded a Nobel Prize in 1906, but did not give
ing a nearby earthquake, Mohorovi˘i´ discovered
cc the usual lecture, and he died very soon after the
that the P and S waves from it were each of two ceremony.
Moivre, Abraham de

Moivre, Abraham de see de Moivre ial metabolism. In this area he introduced the idea
Mond, Ludwig (1839–1909) German–British indus- of operons, groups of genes with related functions
trial chemist. which are clustered together on a chromosome
Son of a prosperous Jewish merchant, Mond stud- and are controlled by a small end-region of the
ied chemistry under Kolbe and Bunsen. From 1858 operon called an operator. This in turn can be made
he had jobs in chemical industry, and devised a inactive by a repressor, which combines with
rather unsatisfactory process for recovering sul- and switches off the operator. The scheme was
phur from the offensive ‘alkali-waste’ of the developed in 1961 to include the idea of messenger
Leblanc soda-making process. He operated this in RNA (mRNA), which carries genetic information
Widnes in the 1860s. In 1872, with J T Brunner from the DNA of the chromosomes (the operon) to
(1842–1919), he began to use the new Solvay process the surface of the ribosomes, where protein synthe-
in his own works at Winnington, Cheshire. This sis occurs. These ideas found much support in
made soda (Na2CO3) from common salt, ammonia experiments on microorganisms; their extension
and carbon dioxide, and displaced the Leblanc to more complex plants and animals is less firmly
process. established. Monod and Jacob, with A Lwoff
In 1889 the corrosion of warm nickel by CO was (1902–94), shared a Nobel Prize in 1965. Monod was
noted and found to be due to the formation of talented and active as a sportsman, musician and
volatile Ni(CO)4. Mond saw this as a novel way of philosopher. His work on the origin of life led him
purifying nickel, by forming and purifying the to argue that it arose by chance and evolved by
tetracarbonyl and then decomposing it by heat; he Darwinian selection through necessity, with no
set up the Mond Nickel Company to do this. Mond overall plan.
Monro, Alexander [muhnroh] (primus, 1697–1767;
became very wealthy and his benefactions included
the re-equipping of the Royal Institution’s labora- secundus, 1733–1817; tertius, 1773–1859) Scottish
tory and the gift of his valuable art collection to the anatomists: an anatomical dynasty.
National Gallery. Brunner, Mond and Company in This dynasty dominated the teaching of medicine
1926 became a major component in the merger and surgery in Edinburgh for 126 years, and did
which formed ICI. much to create and then to increase the fame of the
Monge, Gaspard [mõzh] (1746–1818) French math- ‘Edinburgh School’. The first of the Alexanders,
ematician: founder of descriptive geometry. himself the son of a surgeon, was the first professor
Monge was educated the Collège de la Trinité of anatomy (or any medical subject) there, and
in Lyon, and later at the military academy at under him the number of students increased four-
MĂ©zières, subsequently becoming professor of fold; his son (‘secundus’) was the most able of the
mathematics there. He was an active supporter of three and wrote on the distinction between the
Napoleon, becoming minister of the navy in 1792, lymphatic and circulatory systems and on the phys-
official recorder of Louis XVI’s trial and execution iology of fishes; when he retired he had taught
in 1792–3 and accompanying Napoleon to Egypt 13 404 students, including 5831 from outside
in 1798. An inspired teacher, he helped found Scotland. His son, tertius, wrote much but made no
the École Polytechnique in 1795, becoming its real anatomical discoveries.
Montagnier, Luc [mõtanyay] (1932– ) French
Monge is remembered as the founder of descrip- virologist: discoverer of HIV, the generally accepted
tive geometry, the basis of modern engineering cause of AIDS.
drawing, and for his work on the curvature of sur- Montagnier studied science at Poitiers and sci-
faces. The theory of the class of Monge equations ence and medicine at Paris, becoming MD in 1960.
(equations of the type Ar + Bs + Ct + D = 0), was From 1960–4 he worked in virology as a research
developed by him. He was wide-ranging in his inter- Fellow for the Medical Research Council in the UK,
ests, tackling problems as diverse as partial differ- initially at Carshalton and then in Glasgow.
ential equations, the composition of nitrous acid Returning to France, he headed research groups at
and capillary phenomena. His interest in chemistry Orsay, at the Pasteur Institute and for the National
led him to synthesize water from hydrogen and Centre for Scientific Research (CNRS), specializing
oxygen in 1783 independently of Lavoisier, in virology and becoming professor at the Pasteur
although the two later collaborated on the same Institute in 1985.
problem. Recognition of Montagnier as the discoverer of
Monod, Jacques (Lucien) [monoh] (1910–76) the virus causing AIDS (see panel on p. 260) followed
French molecular biologist: devised theories on the a period of some confusion in work on the cause of
control of gene action. this disease. An early claim for the discovery was
A graduate of Paris, Monod taught zoology there made in 1984 by R Gallo (1937– ) of the US
from 1934, served in the French Resistance in the National Cancer Institute. However, later and
Second World War, and joined the Pasteur Institute rather prolonged investigations on priority made
in 1945, becoming its director in 1971. He worked in the USA showed that the retrovirus causing AIDS
particularly with F Jacob (1920– ) on the problem had been described and photographs of it pub-
of how gene action is switched ‘on’ and ‘off’, espe- lished by Montagnier in May 1983, but the discov-
cially in the enzyme syntheses they control in ery was inadequately appreciated in the USA at that
mutant bacteria, which in turn control the bacter- time. It seems clear that virus samples loaned by
Morgagni, Giovanni Battista

but afterwards did no more in aeronautics. The
‘ballooning craze’ he had begun spread rapidly to
the USA; and the English Channel was crossed in
Moore, Stanford (1913–82) US biochemist: co-
inventor of method for analysing amino acids.
Moore spent his career at the Rockefeller
Institute, having graduated in chemistry from
Vanderbilt University in 1935 and followed this
with a PhD from Wisconsin. A central problem in
protein chemistry is to determine which amino
acids are present in a protein chain, and in what
amount. Only when this is known can work begin
on the sequence of the amino acids in the chain.
With W Stein (1911–80), Moore devised in the early
1950s a general method of analysis. First, the pro-
tein is hydrolysed completely (eg by warm acid) to
give a mixture of amino acids. These are then sepa-
rated from one another by applying the mixture to
the top of a column of ion exchange resin and then
eluting the column with a series of buffer solutions
of progressively changing acidity. The amino acids
emerge separately from the column, can be identi-
fied by their rate of emergence, and the quantity of
each is measured by the intensity of the blue colour
Luc Montagnier
it gives on reaction with ninhydrin. By 1958 Moore
and Stein had devised an ingenious automated
the French group to Gallo’s laboratory in early 1984 analyser to carry out all these steps on a small
contaminated isolates in that laboratory and that sample. The problem of finding the sequence of
Gallo’s discovery was in fact the French virus. By the amino acid groups in the chain can then be
1990s it was also widely agreed that this virus (now attacked by methods such as those used by Sanger
known as HIV, with several strains recognized) is in his work on insulin (1905). The Moore–Stein ana-
the central cause of AIDS, although Montagnier has lytical method was soon used for cases varying
argued that other organisms must be present from the simple heptapeptide evolidine (seven
together with this virus if the death of immune- amino acid groups) to the enzyme ribonuclease
system cells, characteristic of AIDS, is to occur in (124 amino acid groups). Moore, Stein and
the patient. Anfinsen shared the Nobel Prize for chemistry in
Montgolfier, Joseph(-Michel) de (1740–1810) 1972.
Morgagni, Giovanni Battista [mawrganyee]
and (Jacques-)Étienne de Montgolfier [mõgolfyay]
(1745–99) French inventors of the hot air balloon. (1682–1771) Italian anatomist: pioneer of pathology.
These brothers, who both worked in the family Graduating in Bologna, Morgagni taught anatomy
paper-making business, became interested in the there and later in Padua. Although active in
possibility of balloon flight about 1782. Their anatomical research throughout his life, his great
earliest paper models were hydrogen-filled, but the work was not published until he was 80. This was a
gas soon escaped. Their first large model, which survey of about 700 cases, written in the form of 70
reached 25 m, had an envelope of silk taffeta letters to an unknown medical friend. For each
and was lifted by hot air, heated by burning a case, he describes first the clinical features of the
mix of chopped hay and wool. In 1783 they made illness in life and then the post-mortem findings.
a much larger balloon of canvas covered with His object was always to relate the illness to the
paper and used it to raise a sheep, a cock and a lesions found at autopsy. He did not use a micro-
duck in a wicker cage, and later in the year scope. After Morgagni’s book, physicians increas-
two friends ascended, with a brazier to maintain ingly related symptoms to ‘a suffering organ’
the heat. They remained airborne for half an rather than to ‘an imbalance of the four humours’
hour, reaching about 100 m and travelling across and developed methods such as percussion in 1761
Paris; this was the first human flight. Étienne (L Auenbrugger, 1722–1809) auscultation (Läennec,
never ascended in a balloon, and Joseph only once, 1819) and radiography (Röntgen, 1896) to locate
under a huge balloon more than 30 m in diameter lesions causing disease. Morgagni was the first to
in which he flew with six friends. Lighter-than- describe syphilitic tumours of the brain and tuber-
air dirigibles soon began to use hydrogen, and in culosis of the kidney, and to recognize that, where
the 20th-c helium, but hot air balloons have paralysis affects one side of the body only, the
again become popular since the Second World lesion is on the other side of the brain. The modern
War. Joseph also designed a parachute and tested science of morbid anatomy, central to pathology,
it with a sheep dropped from a tower in 1784, begins with him.
Panel: AIDS and HIV


Eastern Europe
& Central Asia
270 000
Western Europe
500 000

East Asia & Pacific
560 000
North America
890 000

South & South-East
North Africa
Caribbean 6.7 million
& Middle-East
330 000
210 000

Latin America
22.5 million
1.4 million

Australia &
New Zealand
12 000

Source: UNAIDS (Joint UN programme on HIV/AIDS)

In 1981, the first reports of a new disease came from origin, with its spread associated with the transfer of
medical centres on the USA’s West Coast. Its key body fluids such as blood or semen during sexual
feature was collapse of the body’s immune system, contact, or from mother to child before birth, or
leading to low resistance to some cancers and to during blood transfusion or by sharing of contami-
infections, such as pneumonia, which are usually nated hypodermic needles. The 100% fatality rate
treatable, but which in these cases were often fatal. and rapidly increasing number of victims (especially
By 1982 it was named as Acquired Immune in Africa) clearly warranted major investigation.
Deficiency Syndrome (AIDS). However, the expansion of AIDS research soon
The AIDS epidemic spread, with deaths from it in exposed some unusual aspects. These included
the USA increasing from 2000 in 1984 to over 10 intense and damaging rivalry between two leading
times as many in 1986. Its victims were then almost research groups (those led by MONTAGNIER at the
entirely among the ‘five H’s’: homosexual men, Pasteur Institute in Paris and by Robert Gallo
heroin addicts, hookers, Haitians and haemophiliacs. (1937– ) of the National Cancer Institute in
At a fairly early stage it was judged to be viral in Washington, DC); the moralistic overtones associated

Morgan, Thomas Hunt (1866–1945) US geneticist:
established chromosome theory of heredity.
Morgan was a product of two prominent Ameri-
can family lines (including his great-grandfather
F S Key, who composed the national anthem) and he
grew up in rural Kentucky with an interest in nat-
ural history. He studied zoology there at the State
College and then at Johns Hopkins University. His
later career was at Columbia, and then at the
California Institute of Technology from 1928.
A quick, humorous and generous man, he is
linked especially with the use in genetics of the
fruit fly, Drosophila melanogaster, and with establish-
ing the chromosome theory of heredity, and the
idea that genes are located in a linear array on chro-
mosomes. When he began his work on genetics he
was doubtful of the truth of Mendel’s views, but his
studies with Drosophila soon convinced him and he
became a vigorous supporter. W Sutton (1877–
1916), in 1902, had suggested that Mendel’s ‘fac-
tors’ might be the chromosomes; Morgan proved T H Morgan
Morse, Samuel

with studies on a mainly sexually-transmitted victims of it had died. By 2000 the UN estimated
disease; and the large sums of money linked with 35 million people were infected with HIV, most in
research on AIDS, on patentable test methods for sub-Saharan Africa but with rising numbers in
identifying its victims and on drugs for its Eastern Europe and in the former USSR.
treatment. As a result of this massive programme, HIV is one
By the early 1990s it was widely agreed that AIDS of the most fully studied of all disease-causing
follows infection by one of the strains of a retrovirus, microorganisms. It is known to be highly variable,
human immunodeficiency virus (HIV), which attacks with its genetic make-up changing frequently to give
the T-lymphocytes (a type of white blood cell). Then, new strains; this adds to the difficulty of devising a
after a period of normally some years, AIDS develops. protective vaccine. But many questions are unan-
Treatment was attempted from 1986 with the costly swered, such as: where and when did the virus origi-
drug AZT (now called zidovudine), but a large-scale nate? Why are so few T-lymphocytes in the blood of
trial begun in 1988 showed by 1993 that this alone most HIV-positive people infected? Why is there a
gave no clear benefits, whether the drug treatment delay of typically 7 years between infection by HIV
began early on patients shown to be HIV-positive or and the onset of AIDS? And why do a very small
was delayed until the full symptoms of AIDS were number of HIV carriers fail to develop AIDS?
present. Problems also arise with test animals. Chimpan-
Despite intensive efforts by epidemiologists to zees are used because they can be infected with HIV.
predict the pattern of spread of the disease, their pro- However, they are costly and not easy to work with,
jected figures have recurrently needed revision; the and their immunology does not model human
number of cases in the early 1990s was much below patients closely – they are not made ill by HIV and do
earlier projections. Predictions that the disease not proceed to develop AIDS. Trials of protective vac-
would spread among heterosexuals have largely cines in human subjects will offer obvious problems.
been unfulfilled in the USA and northern Europe, but Despite the difficulties, the potential problem of AIDS
in parts of Africa have been realized, with up to 50% is so important that great efforts will continue to be
of the general population infected in countries such made both to develop a vaccine against HIV, and to
as Kenya, while significant infection in some less- secure more effective drugs for treatment: AIDS is
developed European countries such as Romania has seen by many workers as the greatest threat to public
occurred through poor medical hygiene. Some geo- health of our time. Anti-retroviral drugs, which are
graphical areas and population groups have palliative but not curative, are widely used in devel-
remained unaffected by the epidemic (eg parts of the oped countries. By the end of 2000, over 5 million
Middle East), for reasons that are unclear. The scale new HIV infections were occurring annually; and
and intensity of research on AIDS is remarkable; by cumulative HIV/Aids-related deaths, worldwide,
1992, over 36 000 research papers had been pub- totalled 21.8 million.
lished on it, over $6000 million had been spent on the
study of the disease and an estimated 500 000

him right, and showed that the units of heredity pose was to test a meteorologist’s theory of the
(the genes) are carried on the chromosomes. With atmosphere. From this he moved to a study of the rel-
his co-workers he established sex-linkage, initially ative atomic mass of oxygen, which he measured to
through the observation that the mutant variety within 1 in 10 000. (Only after his retirement was it
‘white-eye’ occurs almost exclusively in fruit flies known that such measurements represent the
that are male; he also discovered crossover (the ex- weighted average of the stable isotopes of the ele-
change of genes between chromosomes) and he and ment concerned.) Also, he worked with Michelson
his team devised the first chromosome map, in in their famous experiments to detect the ‘ether-
1911 (it showed the relative position of five sex- drift’.
Morse, Samuel (Finley Breese) (1791–1872) US
linked genes; by 1922 they had a map showing the
relative positions of over 2000 genes on the four artist and inventor.
chromosomes of Drosophila). He won a Nobel Prize After education at Yale, Morse concentrated on
in 1933. painting portraits, which he studied in Europe
Morley, Edward Williams (1838–1923) US chemist before his appointment as professor of literature and
and physicist. design in New York’s City University. Always inter-
Morley’s work in science is marked by his passion ested in novelties, he devised an electric telegraph
for precise and accurate measurements. Like his system in 1832 and improved it with technical help
father he was a Congregational minister, but from from Joseph Henry and financial help from Alfred
1882 he taught science in the college that became Vail. In 1843 he set up a 40-mile line from
Western Reserve University in Ohio. His early Washington to Baltimore, fortunately completed
research was on the oxygen content of air; his pur- one day before the Democratic Convention in the
Panel: Long-range communication

LONG-RANGE COMMUNICATION cable link between Washington and Baltimore,
Morse having devised an inker to print the long
Classically, long-range communication was limited to (dashes) and short (dots) signals on a paper tape. To
the speed of horse or boat: but by the time the his fury, operators continued to listen to and interpret
Romans invaded Britain they used a simple hill-top the clicks. Morse, or more probably Vail, devised a
semaphore system, and national alarms were later dot-and-dash code for the alphabet and numerals.
signalled (as was the approach of the Spanish The idea of undersea cabling soon arose, and
armada in 1588) by hill-top beacons. By 1794 in England and France were linked from 1850. The first
France, Chappé's semaphore arms could signal from attempt to lay an undersea cable across the Atlantic
Paris to Lille (about 200 km) in two minutes, while took place in 1857, using the USS Niagara and HMS
the French army used the Sun, or a focused beam Agamemnon. This attempt was abandoned after
from an oil lamp: a precursor of the Royal Navy's multiple breaks of the cable. Two attempts were
Aldis lamp. Static electricity from a friction generator, made in 1858 with improved paying-out machinery
conducted along an insulated wire, offered a and a cable was laid connecting Britain and America;
signalling possibility: it was tested across the Thames but the cable failed after only four weeks. After
at Westminster in 1747, using an earthed boy as further study of the problems and refinancing, the
detector ('his reaction vindicated the anticipated Great Eastern made an attempt in 1865; but a break
result'). occurred half-way across the Atlantic. Then in 1866
Electrical methods became practical with VOLTA'S the Great Eastern succeeded in laying a cable from
invention in 1800 of a battery giving a steady current, Valentia in Ireland to Newfoundland. The ship then
and GAUSS and his friend E H Weber (1795–1878) returned to the buoys marking the spot where the
made daily contact through a simple circuit in first cable had parted the year before, recovered the
TĂĽbingen in the 1830s. The obvious need for speedier end and continued it to Newfoundland, so providing
long-distance communication was for military and two transatlantic telegraph cables.
diplomatic purposes, but commercial possibilities After many difficulties a reliable transatlantic
existed. In 1837, the year of Victoria's coronation, cable was in use, largely as a result of the work of
WHEATSTONE and W F Cooke (1806–79), an Indian William THOMSON (later Lord Kelvin). He saw, as
Army doctor on leave, used a circuit operating a others in the venture did not, that copper for the
'clicker' to cover two miles between Euston and cable must be both pure and of adequate thickness.
Camden Town station, and this is usually seen as the He also saw that, contrary to intuition, rapid sig-
start of modern telegraphy. To detect the arrival of a nalling can be done only with very small currents. The
signal, the wire carrying the signal current was need led him to devise a sensitive galvanometer as
passed close to a magnetic needle, which twitched receiver, which he soon fitted with an ink-jet recorder
when a current arrived. Using several wires each with (the first). Without Kelvin's skill in electrical theory,
its detector, a rather clumsy and slow code allowed a combined with his energy and engineering skill, long-
message to be interpreted from the signals. However, distance cable telegraphy would have stayed a
it took two years before the railway companies failure: for its success he was knighted in 1866, and
installed a telegraph line (Paddington to Slough), and thereafter his inventions brought wealth.
telegraphy needed a newsworthy event before public Before the end of the 19th-c, the UK, encumbered
interest and vigorous line-installation began. by its vast colonial empire, had telegraph or (later)
The event was a murder in 1842 in Slough: the telephone contact with most of it: while after
suspect escaped on a slow train to Paddington. An MARCONI'S transatlantic radio signal of 1901 commu-
alert policeman telegraphed a description, and arrest nication took a further step. By the end of the 20th-c
at London followed; it nearly failed as the description geostationary satellites, the Internet and email made
focused on the suspect being dressed as a Quaker, long-range communication easy (and relatively
but the five-needle telegraph had no Q, and the word cheap) for individual personal use. Morse's laborious
‘kwaker’ was initially incomprehensible. The affair first message of 1844 'WHAT HATH GOD WROUGHT'
did more to advance the spread of telegraphy than would now require quite an extensive answer in the
scientific claims had achieved. In the USA, MORSE and information technology field.
A L Vail (1807–59) in 1843 set up a 55 km overhead MM

latter city. He had in 1838 devised a code of dots and telegraph system in England in 1838, which was
dashes, widely used thereafter, but only of historical quickly extended, and linked with France by cable by
interest by the 1990s. Highly religious, his first mes- 1851.
sage on the new line, to Vail on 24 May 1844, was Another of Morse’s interests was photography. He
‘what hath God wrought’. He later made a fortune learned early from Daguerre of his work, probably
through his patents, despite costly litigation. He made the first photographs in America and, with
earned little in Europe: Wheatstone had set up a his fellow-professor J W Draper, set up a portrait
Mueller, Erwin Wilhelm

studio on the university roof; on sunless days he particular nuclei (Mössbauer spectroscopy). Thus
Fe2+ and Fe3+ can be separately detected in Fe3O4.
instructed students in the new process. His Morse
code remains his main claim to fame. Also, Einstein’s general relativity theory was veri-
Moseley, Henry Gwyn Jeffreys [mohzlee] (1887– fied by measuring the change in wavelength of a
1915) British experimental physicist: showed iden- gamma ray due to its moving from one point of
tity of atomic number and nuclear charge of a gravitational potential to another (1960).
chemical element. Mössbauer shared the 1961 Nobel Prize for
Moseley came from a family of scientists and physics, and afterwards held professorships at the
graduated from Oxford in physics in 1910. At once California Institute of Technology (until 1965) and
he joined Rutherford in Manchester, but in 1913 at Munich.
Mott, Sir Nevill Francis (1905–96) British physicist:
he returned to Oxford to work. In 1914 he visited
Australia, and on the outbreak of the First World discovered aspects of the electronic structure of dis-
War he joined the Royal Engineers and later fought ordered materials.
at Gallipoli. He was shot through the head by a Mott’s parents both worked at the Cavendish
Turkish sniper there during the battle of Suvla Bay. Laboratory and he studied mathematics at
Moseley’s major work was on the characteristic X- Cambridge. He became a lecturer and Fellow there,
rays which W H Bragg and others had shown to be working with Rutherford, and later with Bohr in
produced from metals used as targets in an X-ray Copenhagen. With H Massey (1908–83) he applied
tube. Von Laue’s work had shown that X-ray fre- the new quantum mechanics to the scattering of
quencies could be measured by crystal diffraction, particles in atomic physics, and established this
and Moseley was instructed in this by W L Bragg. In field. At 28 Mott moved to a professorship at Bristol
1913, using a crystal of potassium hexacyanofer- and, influenced by H Jones, became interested in
rate(II) to measure the X-rays, he used over 30 solid-state physics. Close collaboration between
metals (from Al to Au) as targets, and found that the theoreticians and experimentalists led to rapid
X-ray lines changed regularly in position from ele- progress. Metal and alloy behaviour (with Jones)
ment to element, in the order of their position in and ionic crystals (with R W Gurney) formed the
the periodic table. He suggested that this regular subject of books by Mott. Work during the Second
change must mean that the nuclear charge can be World War led to research on dislocation, defects
equated with what he called ‘the atomic number’. and material strengths. In 1954 he moved to the
His work allowed prediction that six elements were Cavendish professorship and started research on
missing from the table and, from their position, the transition between metallic and insulating
their properties and likely association could be pre- behaviour (the Mott transition). He decisively shaped
dicted. As a result, these new elements were soon the Cavendish Laboratory’s research activities, and
sought and found. The relation between an ele- ‘retired’ in 1965.
ment’s X-ray frequency and its atomic number is Then at 60 he returned to full-time research,
known as Moseley’s Law. He was also able to resolve choosing to work on the new area of non-crystalline
confusion over the identity of the rare earth metals, semiconductors and immediately recognizing the
but his major achievement was to link chemical significance of P W Anderson’s papers on elec-
behaviour (as shown by an element’s place in the tronic localization. Once again he published a clas-
periodic table) with the physics of atomic constitu- sic text on his interest (with E A Davis), which
tion. Rutherford called him ‘a born experimenter’ established a complex but rapidly growing area of
who, as Soddy described it, ‘called the roll of the research. Mott was knighted in 1962 and shared the
elements’. 1977 Nobel Prize for physics for his work on the
Mössbauer, Rudolph Ludwig [moesbower] electronic properties of disordered materials.
(1929– ) German physicist: discovered the Mott was one of the major theoretical physicists of
Mössbauer effect, which he used to verify Einstein’s the 20th-c, opening new and difficult areas of solid-
general relativity theory. state physics and materials science. He influenced a
Mössbauer was taking his doctorate at the Max generation in showing how to model the complexity
Planck Institute for Medical Research in Heidelberg of physical problems such as fracture of metals or
(1955–7) when he discovered what is now called the electronic processes in disordered semiconductors.
Mueller, Erwin Wilhelm [müler] (1911–77)
Mössbauer effect. When an atom absorbs a gamma
ray it recoils and, by energy conservation, the wave- German–US physicist: invented the field-ion micro-
length of the re-emitted gamma ray is altered. scope.
However, Mössbauer found that at low tempera- A graduate in engineering from Berlin, Mueller
tures one can avoid (for a certain fraction of gamma worked for industrial laboratories in Berlin and for
ray processes) the excitation of vibrational motions the Fritz Haber Institute until 1952 when he joined
in a solid. In such processes, the lattice recoils as a Pennsylvania State University. In 1936 he invented
whole and recoil shifts of the energy are absent in the field-emission microscope, in which a high neg-
the associated gamma-lines; in effect recoil-less ative voltage is applied to a fine metal tip held in a
nuclear resonance provides very high precision (1 vacuum near a phosphorescent screen. Electrons
in 1012) in the absorbed and re-emitted gamma ray emitted from the tip travel to the screen and form
wavelength. This precision allows detection of a highly magnified image of the tip’s surface, allow-
different electronic environments surrounding ing study of conditions at that point of atoms and
MĂĽller, Hermann Joseph

molecules provided they are stable enough to sur- Bonn prize question: does the fetus breathe in the
vive the conditions at the tip. In 1951 he devised a womb? Experiments on a ewe showed that the
field-ion microscope, in which the metal tip is held blood-colour entering and leaving the fetus indi-
positive in gas at a low pressure. Gas adsorbed on cated that it did respire. (Afterwards MĂĽller was
the tip becomes ionized, and the resulting positive antagonistic to vivisection on warm-blooded ani-
ions are repelled from the tip and form the image. mals, although he was a great user of frogs.) His later
The resolution is improved by cooling the tip with work was wide-ranging; he studied electrophysiol-
liquid helium, and in this way in 1956 Mueller was ogy, the sensory system of the eye, the glandular
able to obtain well-resolved images from atoms for system, the human embryo and the nervous system.
the first time. He showed the value of microscopy in pathology,
Müller, Hermann Joseph [müler] (1890–1967) US developing procedures now used in daily clinical
geneticist: discoverer of use of X-rays to induce work, especially on tumours. He worked on classifi-
genetic mutation. cation in zoology, especially on marine animals. He
MĂĽller became an enthusiast for genetics at 16; proposed the law of specific nerve energies in 1840.
he had already founded the first science club at his This states that each sensory system will respond to
Harlem school, and won a scholarship to Columbia a stimulus (whether this is mechanical, chemical,
University. By 1915 he began his experiments on thermal, or electrical) in the same way, specific to
spontaneous gene mutation, a key effect in the itself. Thus the eye always responds with a sensation
study of genetics, under the guidance of T H of light, however it is stimulated; the ear with a sen-
Morgan, the leading American geneticist. MĂĽller sation of sound, and so on. Man does not perceive
already saw natural mutations as not only rare but the external world directly, but only the effects on
usually both detrimental (often lethal) and reces- his sensory systems. ‘In intercourse with the exter-
sive; and he saw the gene itself as the true basis of nal world we continually sense ourselves’ – an
both evolution and of life itself, as its ability to important statement for philosophy.
reproduce itself was the central property of living His many pupils include Schwann, Du Bois-
matter. In 1926 he achieved the abundant and easy Reymond, Helmholtz, J Henle (1809–85) and
production of mutations by use of X-rays, which Virchow. He is widely regarded as the greatest of
hugely increased the scope of genetic studies. He all physiologists.
Müller, Paul Hermann [müler] (1899–1965) Swiss
concluded, correctly, that mutation is in essence no
more than a chemical reaction. He used the fruit fly chemist: developed DDT as an insecticide.
Drosophila for much of his work, but the method can Educated in Basle, MĂĽller spent his career from
be applied to reproductive cells of any kind. Since 1925 with the Swiss chemical company of J R Geigy.
then, chemicals (such as colchicine, and mustard From 1935 he attempted to find an insecticide that
gas) have been used in place of X-rays or other high- would be rapid and persistent but harmless to
energy radiation to induce mutations. plants and to warm-blooded animals. By 1940 he
MĂĽller moved to Germany in 1932 but in 1934 he had patented as an insecticide a chemical first
moved on to the USSR, only to find its political cli- made in 1873; it was dichlorodiphenyltrichloro-
mate even more unhappy for him; Edinburgh was methane (‘DDT’), which is cheaply and easily pro-
his home from 1937–40 and thereafter the USA. His duced. This was highly effective, eg in killing lice
influence in genetics was very great and his X-ray (the carriers of typhus fever) and so preventing epi-
work won him the Nobel Prize in 1946. He was much demics at the end of the Second World War. For 20
concerned both that environmental radiation from years it was much used, but fell into partial dis-
many sources can injure human genes and that favour when the emergence of resistant insect
modern medicine tends to preserve mutants in the species limited its effectiveness, while it was also
population, and he advocated sperm banks to main- found to have a damaging effect on some other ani-
tain and improve the human gene pool. mals; its persistence in food chains was seen as a
Müller, Johannes Peter [müler] (1801–58) German disadvantage and by the 1970s its use was banned
physiologist: made wide-ranging discoveries, con- or limited in some advanced countries. MĂĽller was
tributing also to anatomy, zoology and neurology. awarded a Nobel Prize in 1948.
Mulliken, Robert (Sanderson) (1896–1986) US
The MĂĽller family were Moselle wine-growers,
but Johannes’s father was a prosperous shoemaker chemical physicist: developed molecular orbital
in Coblenz. The boy entered the newly founded uni- theory and investigated molecular spectroscopy.
versity at Bonn in 1819, and his combination of An organic chemist’s son, Mulliken graduated in
talent and great ambition soon attracted attention. chemistry at MIT in 1917, went on to study poison
In 1826 he became a professor there. When a post gases and then in 1919 began work in Chicago on a
became vacant in Berlin, he took the remarkable problem in chemical physics (isotope separation).
step of proposing himself for the job, and got it. He Except for some research visits he was to spend the
was a frequent victim of depression and his death rest of his long career at Chicago, working on a
was probably due to suicide, but this is uncertain variety of topics in chemical physics involving mol-
because he had forbidden an autopsy. ecular spectra and quantum theory. By 1932 Bohr,
When well, he was intensely productive as a phys- F Hund (1896– ) and others had done much to
iologist. His first work covered problems of locomo- show how energy levels in atoms could be under-
tion in animals. Then, in 1820, he attacked the stood in theory and related experimentally to
Muybridge, Eadweard James

atomic spectra. Mulliken extended these ideas to
molecules. His central idea was that, in a molecule,
the electrons that bind the nuclei together move in
the field produced by two or more nuclei; the
atomic orbitals (a word he devised) become molec-
ular orbitals extending over these nuclei. He
showed how the energies of these orbitals could be
found from the spectra of the molecules. These
ideas formed the basis of molecular orbital (MO)
theory and were developed by Mulliken, and by
Coulson, HĂĽckel and others in Europe, to become
the major approach to understanding the bonds
between atoms in molecules. He was awarded the
Nobel Prize for chemistry in 1966.
Mullis, Kary (Banks) (1944– ) US biochemist:
devised the polymerase chain reaction for amplifi-
cation of traces of DNA.
Mullis studied chemistry at the Georgia Institute
of Technology and then biochemistry at Caltech, and
Walter Munk
afterwards joined a biotechnology company, Cetus.
His fame and the Nobel Prize for chemistry which
Munk, Walter Heinrich [munk] (1917– ) US
he shared in 1993 stem from an idea that came to
him during a 3-hour night drive in 1983. This con- oceanographer and geophysicist: improved under-
cerned the problem of identifying genes (or other standing of the Earth’s rotation.
fragments of DNA), especially when only a small Born in Vienna, Munk emigrated to America
sample is available. His scheme was to first break up when he was 16. He was educated at the California
the DNA by a known technique using restriction Institute of Technology and the University of
endonucleases, which split the DNA at specific California, and held positions at Scripps Institution
base-pairs to give a mixture of oligonucleotides: of Oceanography of the University of California.
these are of modest molecular size (a few dozen Munk’s special interest was the rotation of the
base-pairs) and contain the genes, in the form of Earth and its variability. In 1961, together with G J
specific base sequences. F MacDonald (1929– ), he showed how a variety of
The Mullis idea was to take these oligonucleotides geophysical factors – including tides, air circula-
and use a chemical method whereby they repli- tion, and glaciation – all have measurable effects
cated themselves, employing relatively uncompli- on the length of the day, which varies by roughly
cated reagents and allowing the synthesis to 0.002 s between summer and winter.
Murchison, Sir Roderick Impey (1792–1871)
proceed repetitively on the products. His method
for doing this was subtle but experimentally simple British geologist: first identified the Silurian,
(a ‘one-pot’ cycle of reactions whose result would be Devonian and Permian periods.
to continually amplify the starting oligonu- Murchison entered the army at 15, served briefly in
cleotide). Each cycle, doubling the DNA fragments, the Peninsular War and then married and settled
took only 1–2 minutes, so in a few hours one mole- near Durham to follow his interest in foxhunting. At
cule gave 100 billion replicas of itself. A key mater- 32 he became friendly with Davy and his enthusiasm
ial, used as a catalyst, was DNA polymerase, moved to science and particularly to geology, where
discovered by Kornberg in 1955. Within a year he had a flair for stratigraphy. He made a series of
Mullis had tested and improved the method; he arduous geological field explorations, at times with
named it the polymerase chain reaction (PCR); it Sedgwick or Lyell, and in 1839 he produced his
has been widely used ever since. These uses include major book The Silurian System, based on his study of
very sensitive tests for genes, based on PCR’s ability the greywackes of South Wales. With Sedgwick he
to amplify a trace of DNA to a handlable quantity, established the Devonian system in southwest
valuable in forensic work to identify a small hair or England, and an expedition to Russia in 1841 led him
semen sample and in studies on DNA traces from to define another world-wide system, the Permian,
extinct fossil animals, such as insects trapped in based on rock stratification in the Perm area.
ancient amber, and from dinosaur bones. After about 1840 he became arrogant and intoler-
His recorded interests include artificial intelli- ant, and in disputes with Sedgwick and others he
gence, computing, photography and cosmology. treated the Silurian as personal property. He was
Mullis has acquired a notable reputation as an eccen- always totally opposed to Darwin’s theory of evolu-
tric. Never a conformist, he doubts if the HIV virus tion. In 1855 he succeeded de la Beche as director-
alone causes AIDS. Now an independent consultant, general of the Geological Survey.
Muybridge, Eadweard James, originally Edward
he set up a company (Stargene) to make and market
amplified samples of the DNA of entertainment James Muggeridge [moybrij] (1830–1904) British–
stars, in lockets and bracelets. He believes Nobel US photographer: pioneered use of photography to
Prizes should be home-delivered by royal messenger. study animal locomotion.
Muybridge, Eadweard James

In 1872 ex-governor Leland Stanford of California
commissioned Muybridge to photograph his horses
in motion, to resolve an argument about the
horse’s gait, but his first efforts failed to give deci-
sive results. (Stanford was rich; his will bequests
included 2 million dollars to ‘the Leland Stanford
Junior University’, named in memory of his son).
Muybridge was interrupted in this work by his trial
for the murder of his wife’s lover. He was acquitted,
and after a prudent absence he returned to the
problem in the late 1870s and soon proved
that a galloping horse has all its feet off the ground
at times (as Stanford had claimed). He used a bat-
tery of up to 24 small cameras with shutters
speeded to 1/500 s and released by clockwork or by
threads successively broken by the horse.
His books and lectures on animal locomotion
broke new ground and attracted both scientific and
popular audiences. By the 1880s, sponsored by the
University of Pennsylvania, he was using up to 36
cameras and the new faster dry plates to study run-
ning and jumping men, as well as animals; his book
Animal Locomotion (1887) contains over 20 000 fig-
Eadweard Muybridge showing his zoopraxiscope in 1889.
ures. Despite its high price, the book sold well,
His cinema system was not a success, but his photographic
probably because the largest category of pho-
studies of animal motion were a useful innovation.
tographs showed nude women engaged in such
actions as falling, jumping and throwing water at
Born Edward James Muggeridge, Muybridge one another. Muybridge devised projection equip-
believed the adopted spelling was the Anglo-Saxon ment for sequential pictures (the Zoopraxiscope,
form of his name. Muybridge emigrated to 1879) and his Zoopraxographical Hall in Chicago in
California when he was 22 and became a 1893 has been claimed as ‘the world’s first motion
professional photographer. His ‘composite’ land- picture theatre’. However, a cinema as we now
scapes were impressive, and by about 1870 he was know it was first opened by the Lumière brothers in
the official photographer to the US Government. Paris in late 1895.

A typical set of images from Muybridge’s Animal Locomotion.

Naegeli, Carl Wilhelm von [nayglee] (1817–91) chosen was not always convenient, leading Briggs
German botanist: made early studies of cell divi- to calculate, in 1617, a table of logarithms to base
sion and plant growth. 10. In the same year Napier also described a system
Educated in ZĂĽrich, Naegeli gave up medicine to of rods (‘Napier’s bones’) designed for practical
study botany under Candolle and then Schleiden. multiplication and division. Kepler, then involved
From 1857 he was professor at Munich. In 1842 he in the tedious process of calculating planetary
had studied pollen formation with great care, accu- orbits, was largely responsible for the introduction
rately describing cell division, including division of of logarithms to the continent. The Swiss J BĂĽrgi
the nucleus. He saw the chromosomes but regarded (1552–1632) had the idea of logarithms about the
them as unimportant; and when Mendel sent him same time as Napier but did not publish until 1620.
a copy of his classic paper on peas, Naegeli disre- Electronic calculators have now displaced ‘log
garded it. Naegeli’s views on evolution were tables’ and slide rules for calculation.
Natta, Giulio (1903–79) Italian polymer chemist:
broadly Darwinian, but he supported Lamarck in
believing that evolution occurs in jumps rather developed theory and technology of stereospecific
than by gradual variation. Oddly, he also believed polymerization.
in spontaneous generation of a rather special sort. Natta graduated in chemical engineering at
In plant taxonomy he did good work, but his best Milan Polytechnic and after short periods at three
work was on plant growth; he recognized the dis- Italian universities returned to Milan in 1938 as
tinction between meristematic tissue and struc- professor of industrial chemistry. From 1938 his
tural tissue, and he worked on cell ultrastructure. work was directed to new polymers, initially syn-
Nansen, Fridtjof (1861–1930) Norwegian explorer thetic rubbers. In 1953 he began work with the cat-
and biologist: pioneer of arctic exploration. alysts shown by K Ziegler (1898–1973) to polymerize
Nansen graduated in zoology from the University alkenes under mild conditions. By 1954 he had
of Christiania (now Oslo), later being appointed shown that these catalysts can give polymers that
professor of zoology and then of oceanography at are stereoregular, ie the repeating unit in the poly-
Christiania. Nansen is known as a pioneer of Arctic mer chains has a recurring and regular space-
exploration. In 1888 he crossed the Greenland ice arrangement (stereochemistry). This feature
sheet for the first time, demonstrating that it cov- (named as ‘tacticity’ by Natta’s wife) is important
ered the entire island. Between 1893 and 1896 he because a suitable stereoregular form has commer-
made an epic voyage in the Fram, a specially cially useful properties of high strength and melt-
strengthened ship which he allowed to freeze into ing-point. He found that propene could be made to
the ice pack and to be carried by the currents give an isotactic polypropylene well-suited for
around the Arctic Ocean, reaching 87°57’N, further moulded products. Both the ideas and the products
north than anyone had been before. He later did devised by Natta have been much used; with
further oceanographic work in the Barents and Ziegler, he shared a Nobel Prize in 1963.
Néel, Louis (Eugène Félix) [nayel] (1904–2000)
Kara Seas and in the north-east Atlantic. An ardent
nationalist, Nansen played an important part in French physicist: discovered antiferromagnetism.
the separation of Norway from Sweden in 1905 and Néel graduated from the École Normale Supé-
became the first ambassador to Britain of the newly rieure and worked under P Weiss (1865–1940) at the
independent state. In 1922 he was awarded the University of Strasbourg. In 1940 he moved to
Nobel Peace Prize in recognition of his humanitar- Grenoble and became the driving force in making
ian work for famine relief and refugee aid after the it one of the most important scientific centres in
First World War. France, becoming director of the Centre for
Napier, John (1550–1617) Scottish mathematician: Nuclear Studies there in 1956.
inventor of logarithms. Néel’s research was concerned with magnetism
Napier was educated in France and at the Univer- in solids. He predicted in 1936 that a special type of
sity of St Andrews. He came from a landed family magnetic ordering called ‘antiferromagnetism’
and pursued mathematics as a hobby, his other should exist. Whereas unpaired electron spins
interests being religious controversy and the inven- align in a ferromagnet (eg Fe), they are arranged
tion of machines of war. up-down-up-down from site to site in an antiferro-
His studies of imaginary roots led him to develop magnetic lattice (eg in FeO). Above a critical
the principle of the logarithm, and he then spent temperature, the NĂ©el temperature, the antiferro-
20 years computing tables of them (in the course of magnetic substance then becomes paramagnetic.
which he also developed modern decimal nota- This was experimentally confirmed in 1938, with
tion), publishing his results in 1614. His work was full neutron diffraction confirmation in 1949. NĂ©el
enthusiastically received, but the base that he had also first suggested (1947) that antiferromagnetism
Ne’eman, Yuval

could occur with unequal up-and-down moments acquired a country estate and indulged his passion
(ferrimagnetism) as in some ferrites. (These ceram- for the new enthusiasm, the motor car.
ics are important in magnetic devices such as the Of his many contributions to chemical thermo-
record–erase heads in audiotape and videotape dynamics, the best-known is his ‘heat theorem’
recorders, and computer hard disk drives. The which became the third law of thermodynamics:
paint used on stealth aircraft contains ferrite crys- all perfect crystals have the same entropy at
tals, which absorb radar signals, conferring invisi- absolute zero. He argued that it was the last law of
bility to radar detection. An ancient ferrite is thermodynamics; because the first law had three
lodestone, used in primitive compasses.) The mag- discoverers, the second two, and the third, one
netic domains foreseen by NĂ©el were imaged in (Nernst). In fact the zeroth law was yet to be for-
2000 in a ferrite, lanthanum iron oxide, and found mally enunciated and has no single discoverer.
to be a few hundred nanometres in size. Néel was Nernst’s widespread research in physical chem-
awarded the Nobel Prize for physics in 1970. He also istry included much electrochemistry; the concept
studied the past history of the Earth’s magnetic field. of solution pressure is due to him, and much of the
Ne’eman, Yuval (1925– ) Israeli particle physicist: thermodynamic treatment of electrochemistry, as
developer of particle theory. well as contributions to the theory of indicators
Ne’eman is unusual in having careers in engi- and buffer action. In photochemistry he proposed
neering, physics, politics and military intelligence, the now familiar path for the fast reaction between
usually being active in at least two of these appar- hydrogen and chlorine, involving a chain reaction
ently disparate areas concurrently. He graduated in based on atomic chlorine.
engineering at the Technion (the Israel Institute of Nernst was kindly but immodest, and he and his
Technology) in Haifa in 1945 and then began a mil- family were known as the most hospitable acade-
itary career, becoming deputy head of the intelli- mic family in Berlin. In the First World War he saw
gence branch of the Israeli forces in 1955. After the early that Germany must lose, and tried to per-
Israeli–Arab war, wishing to work in theoretical suade the Kaiser and others to seek peace, without
physics, he arranged with General Dayan to become success. Both his sons were killed in the war.
a military attaché at the Israeli Embassy in London, Afterwards he declined an offer to become ambas-
which enabled him to work also at Imperial College sador to the USA. He was awarded a Nobel Prize in
with Salam (his first intention had been to work at 1920. From the beginning he opposed Hitler’s poli-
King’s College with Bondi on relativity, but the cies; unsuccessful, he retired to his country estate.
time required to travel across London to King’s was Anecdotes about him, from his many distinguished
too great, whereas Imperial College is close to the pupils, are legion. No-one in his time held a wider
Embassy). or deeper grasp of physical chemistry or did more
His interest in particle classification and in group to advance it.
Neumann, John (János) Von see Von Neumann
theory developed under Salam’s guidance, and in
Newlands, John Alexander Reina (1837–98)
1961 he published a valuable general classification
of nuclear particles; Gell-Mann arrived at a similar British chemist: devised primitive form of periodic
scheme at about the same time. The quark model of classification of chemical elements.
nuclear structure made the new concepts widely Newlands studied chemistry in London under
known. Hofmann and later became an analytical chemist,
After founding and heading the physics depart- specializing in sugar chemistry. In 1860 he spent a
ment at Tel-Aviv University Ne’eman became presi- period in Italy as a volunteer in Garibaldi’s army;
dent of the university from 1972–5 and concurrently his mother, Mary Reina, was of Italian descent.
director of the Center for Particle Theory at the In 1864, and during the next 2 years, Newlands
University of Texas at Austin (1968– ). Then in showed that if the chemical elements are numbered
1981 he founded the Tehiya political party, and as in the order of their atomic weight and tabulated,
its chairman was elected to the Knesset (the Israeli then ‘the eighth element starting from a given one
parliament), becoming minister of science and is a kind of repetition of the first, like the eighth
development in the cabinet 1982–4, and head of the note in an octave of music’. Thus his law of octaves
Israeli Space Agency from 1983. (as he called it) showed the halogens grouped
Nernst, (Hermann) Walther (1864–1941) German together and the alkali metals in another group. He
physical chemist: pioneer of chemical thermody- did not leave gaps for undiscovered elements and
namics and discoverer of the third law of thermo- his rigid scheme had some unacceptable features
dynamics. and was much criticized; one critic asked him deri-
Nernst studied physics in four German universities sively if he had tried an alphabetical arrangement.
and worked in two more, becoming increasingly con- In 1869 Mendelayev published a table which is
cerned with the application of physics to chemical essentially modern; Newlands then tried to claim
problems. He was appointed to a professorship in priority and was so persistent that the Royal Society
Berlin in 1905. His early researches on electrochem- awarded him its Davy Medal in 1887. They did not
istry, and on thermodynamics, established his fame. elect him to their Fellowship. Newlands certainly
In 1904 he devised an electric lamp which he sold for had a part of the periodic classification in mind, but
a million marks. The lamp was soon superseded for he did not develop the idea as effectively as did
lighting by Edison’s, but it had made Nernst rich. He Mendelayev or J L Meyer (1830–95).
Newton, Sir Isaac

years of 1665 and 1666, for in those years I was in
the prime of my age for invention, and minded
Mathematics and Philosophy more than at any
time since.’
On returning to Trinity College, he was elected a
Fellow (1667) and succeeded Isaac Barrow as
Lucasian Professor in 1669 at the age of 26. He was
made a Fellow of the Royal Society in 1672. During
1669–76 Newton presented many of his results in
optics and became engaged in controversies con-
cerning them. In 1679 he began to correspond with
Hooke, renewing his interest in dynamics and solv-
ing the problem of elliptical planetary motion dis-
covered by Kepler. Halley visited Newton in 1684
and persuaded him to write a work on dynamics,
which was written within 18 months; his Philosophiae
Isaac Newton: his earliest portrait, at age 46, by Sir
naturalis principia mathematica (1687, The Mathema-
Godfrey Kneller. Newton was writing the Principia at
tical Principles of Natural Philosophy) – the
about this time. Many later portraits exist, although
‘Principia’. It is the most important and influential
Newton claimed to detest being painted.
scientific book ever written.
From that point Newton’s mathematical interests
Newton, Sir Isaac (1642–1727) English physicist waned, giving place to theology (ironically, bearing
and mathematician: discovered the binomial theo- in mind his college, he seems to have been anti-
rem, invented calculus and produced theories of trinitarian) and involvement in political life. He
mechanics, optics and gravitation. also spent much time and effort on alchemy, with-
Newton was born prematurely in the year Galileo out result. In 1687 he courageously accompanied
died, 3 months after the death of his father, the the vice-chancellor to London to defend the univer-
owner of Woolsthorpe Manor in Lincolnshire. sity against illegal encroachments by James II. In
He was left in the care of his grandmother at 1692 Newton ‘lost his reason’, as he phrased it;
Woolsthorpe when his mother remarried, and came probably he suffered a period of severe depression.
under the influence of his uncle, who recognized Then his interests turned to London and, via his
his talents. Newton went to the grammar school in friendship with Charles Montague, Fellow of the
Grantham and after farming at Woolsthorpe for 2 Royal Society and first earl of Halifax, Newton
years was sent to Trinity College, Cambridge, in became Warden and then Master of the Mint in
1661. He remained there for nearly 40 years. It is 1696 and 1698 respectively, skilfully reforming the
clear that as a young man Newton was what we currency. He was knighted for this in 1705. In
would now describe as rather a hippy. A contempo- London, a young niece became his housekeeper.
rary recalled that he often ‘dined in college … stock- She was Catherine Barton, described as beautiful,
ings untied, head scarcely combed’. His portrait by charming and witty, and the mistress of Charles
Kneller, made when he was 46, still shows him in Montague. Newton’s duties at the Mint included
casual dress and with very long hair. supervising the recoinage and, rather oddly, the
As a student Newton attended Isaac Barrow’s capture, interrogation and prosecution of counter-
(1630–77) lectures on mathematics. In 1665 the feiters.
Great Plague caused him to return to his isolated In 1701 he resigned the Lucasian professorship
home at Woolsthorpe. Here he worked on many of and his fellowship at Trinity, although he
the ideas for which he is so famous, during what remained president of the Royal Society from 1703
became known as his ‘miraculous year’. Later until his death. He was elected a Whig member of
(c.1716) Newton wrote in his notebooks: Parliament for the university, but was not very
‘In the beginning of the year 1665 I found the active politically.
method for approximating series and the rule for Much of Newton’s last 20 years were spent in
reducing any dignity [power] of any binomial to acrimonious debate over priority in scientific dis-
such a series [ie the binomial theorem]. The same coveries with Flamsteed and Leibniz, and in this
year in May I found the method of tangents of Newton showed both ruthlessness and obsessive-
Gregory and Sulzius, and in November had the ness. Following a painful illness (due to a gallstone),
direct method of Fluxions [ie the elements of the he died in 1727, and is buried in Westminster
differential calculus], and in the next year in Abbey. He had been remarkably fit, lacking only
January had the Theory of Colours, and in May fol- one tooth and not needing spectacles, even in old
lowing I had entrance into the inverse method of age, and reasonably wealthy. He seems to have had
Fluxions [ie integral calculus], and in the same year no romantic or imaginative life outside science.
I began to think of gravity extending to the orb of Asked his opinion on poetry, he replied ‘I’ll tell you
the Moon … and … compared the force requisite to that of Barrow; he said that poetry was a kind of
keep the Moon in her orb with the force of gravity ingenious nonsense.’
at the surface of the Earth…. All this was in the two Newton’s researches on mechanics display great
Nicholson, William

mastery and established a uniform system based on mirrors rather than lenses to gather light and
the three laws of motion: (1) a body at rest or in uni- achieve magnification (see panel on Telescopes,
form motion will continue in that state unless a p. 95).
force is applied; (2) the applied force equals the rate Newton’s name is linked with a variety of matters
of change of momentum of the body; (3) if a body in physics, in addition to those already noted (eg
exerts a force on another body there is an equal but the laws of motion). Thus the SI unit of force, the
opposite force on the first body. From these Newton newton (N), is based on the second law, in the form
explained the collision of particles, Galileo’s results which defines the force F which produces a con-
on falling bodies, Kepler’s three laws of planetary stant acceleration a in a body of mass m, by the rela-
motion and the motion of the Moon, Earth and tion F = ma. The newton is the force which produces
an acceleration of 1 m s–2 when it acts on a mass of
tides. The deductions were made using calculus,
but were proved geometrically in the Principia to 1 kg.
clarify it for contemporary readers. The general In fluid mechanics, Newtonian fluids are those


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