Henry Moseley
   HOME

TheInfoList



OR:

Henry Gwyn Jeffreys Moseley (; 23 November 1887 – 10 August 1915) was an English
physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...
, whose contribution to the
science Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence ...
of
physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which ...
was the justification from physical laws of the previous empirical and
chemical A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., w ...
concept of the
atomic number The atomic number or nuclear charge number (symbol ''Z'') of a chemical element is the charge number of an atomic nucleus. For ordinary nuclei, this is equal to the proton number (''n''p) or the number of protons found in the nucleus of ever ...
. This stemmed from his development of
Moseley's law Moseley's law is an empirical law concerning the characteristic x-rays emitted by atoms. The law had been discovered and published by the English physicist Henry Moseley in 1913-1914. Until Moseley's work, "atomic number" was merely an element's ...
in X-ray spectra. Moseley's law advanced atomic physics, nuclear physics and quantum physics by providing the first experimental evidence in favour of Niels Bohr's theory, aside from the hydrogen atom spectrum which the Bohr theory was designed to reproduce. That theory refined
Ernest Rutherford Ernest Rutherford, 1st Baron Rutherford of Nelson, (30 August 1871 – 19 October 1937) was a New Zealand physicist who came to be known as the father of nuclear physics. ''Encyclopædia Britannica'' considers him to be the greatest ...
's and
Antonius van den Broek Antonius Johannes van den Broek (4 May 1870, Zoetermeer – 25 October 1926, Bilthoven) was a Dutch amateur physicist notable for being the first who realized that the number of an element in the periodic table (now called atomic number) correspond ...
's model, which proposed that the
atom Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons. Every solid, liquid, gas, a ...
contains in its nucleus a number of positive nuclear charges that is equal to its (atomic) number in the periodic table. This remains the accepted model today. When
World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
broke out in
Western Europe Western Europe is the western region of Europe. The region's countries and territories vary depending on context. The concept of "the West" appeared in Europe in juxtaposition to "the East" and originally applied to the ancient Mediterranean ...
, Moseley left his research work at the
University of Oxford , mottoeng = The Lord is my light , established = , endowment = £6.1 billion (including colleges) (2019) , budget = £2.145 billion (2019–20) , chancellor ...
behind to volunteer for the Royal Engineers of the
British Army The British Army is the principal land warfare force of the United Kingdom, a part of the British Armed Forces along with the Royal Navy and the Royal Air Force. , the British Army comprises 79,380 regular full-time personnel, 4,090 Gurk ...
. Moseley was assigned to the force of
British Empire The British Empire was composed of the dominions, colonies, protectorates, mandates, and other territories ruled or administered by the United Kingdom and its predecessor states. It began with the overseas possessions and trading posts e ...
soldiers that invaded the region of Gallipoli, Turkey, in April 1915, as a
telecommunications Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that fe ...
officer. Moseley was shot and killed during the Battle of Gallipoli on 10 August 1915, at the age of 27. Experts have speculated that Moseley could otherwise have been awarded the
Nobel Prize in Physics ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then " ...
in 1916.


Biography

Henry G. J. Moseley, known to his friends as Harry, was born in Weymouth in
Dorset Dorset ( ; archaically: Dorsetshire , ) is a county in South West England on the English Channel coast. The ceremonial county comprises the unitary authority areas of Bournemouth, Christchurch and Poole and Dorset. Covering an area of , ...
in 1887. His father Henry Nottidge Moseley (1844–1891), who died when Moseley was quite young, was a biologist and also a professor of
anatomy Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having it ...
and
physiology Physiology (; ) is the scientific study of functions and mechanisms in a living system. As a sub-discipline of biology, physiology focuses on how organisms, organ systems, individual organs, cells, and biomolecules carry out the chemical ...
at the University of Oxford, who had been a member of the ''Challenger'' Expedition. Moseley's mother was Amabel Gwyn Jeffreys, the daughter of the Welsh
biologist A biologist is a scientist who conducts research in biology. Biologists are interested in studying life on Earth, whether it is an individual Cell (biology), cell, a multicellular organism, or a Community (ecology), community of Biological inter ...
and conchologist
John Gwyn Jeffreys John Gwyn Jeffreys FRS (18 January 1809 – 21 January 1885) was a British conchologist and malacologist. Biography John Gwyn Jeffreys was born on 18 January 1809, at Swansea, Wales. He was the eldest son of J. Jeffreys of Fynone, Glamorgan. ...
. She was also the British women's champion of chess in 1913. Moseley had been a very promising schoolboy at
Summer Fields School Summer Fields is a fee-paying boys' independent day and boarding preparatory school in Summertown, Oxford. It was originally called Summerfield and used to have a subsidiary school, Summerfields, St Leonards-on-Sea (known as "Summers mi"). H ...
(where one of the four "leagues" is named after him), and he was awarded a King's scholarship to attend
Eton College Eton College () is a public school in Eton, Berkshire, England. It was founded in 1440 by Henry VI under the name ''Kynge's College of Our Ladye of Eton besyde Windesore'',Nevill, p. 3 ff. intended as a sister institution to King's College, ...
.- JSTOR article; permission required In 1906 he won the chemistry and physics prizes at Eton. In 1906, Moseley entered Trinity College of the University of Oxford, where he earned his
bachelor's degree A bachelor's degree (from Middle Latin ''baccalaureus'') or baccalaureate (from Modern Latin ''baccalaureatus'') is an undergraduate academic degree awarded by colleges and universities upon completion of a course of study lasting three to six ...
. While an undergraduate at Oxford, Moseley joined the Apollo University Lodge. Immediately after graduation from Oxford in 1910, Moseley became a demonstrator in physics at the
University of Manchester , mottoeng = Knowledge, Wisdom, Humanity , established = 2004 – University of Manchester Predecessor institutions: 1956 – UMIST (as university college; university 1994) 1904 – Victoria University of Manchester 1880 – Victoria Univ ...
under the supervision of Sir Ernest Rutherford. During Moseley's first year at Manchester, he had a teaching load as a
graduate teaching assistant A teaching assistant or teacher's aide (TA) or education assistant (EA) or team teacher (TT) is an individual who assists a teacher with instructional responsibilities. TAs include ''graduate teaching assistants'' (GTAs), who are graduate stud ...
, but following that first year, he was reassigned from his teaching duties to work as a graduate research assistant. He declined a fellowship offered by Rutherford, preferring to move back to Oxford, in November 1913, where he was given laboratory facilities but no support.


Scientific work

Experimenting with the energy of beta particles in 1912, Moseley showed that high potentials were attainable from a radioactive source of radium, thereby inventing the first
atomic battery An atomic battery, nuclear battery, radioisotope battery or radioisotope generator is a device which uses energy from the decay of a radioactive isotope to generate electricity. Like nuclear reactors, they generate electricity from nuclear en ...
, though he was unable to produce the 1MeV necessary to stop the particles. In 1913, Moseley observed and measured the
X-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10  picometers to 10  nanometers, corresponding to frequencies in the range 30&nb ...
spectra of various
chemical element A chemical element is a species of atoms that have a given number of protons in their nuclei, including the pure substance consisting only of that species. Unlike chemical compounds, chemical elements cannot be broken down into simpler sub ...
s (mostly metals) that were found by the method of diffraction through
crystal A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macro ...
s. This was a pioneering use of the method of
X-ray spectroscopy X-ray spectroscopy is a general term for several spectroscopic techniques for characterization of materials by using x-ray radiation. Characteristic X-ray spectroscopy When an electron from the inner shell of an atom is excited by the energy o ...
in physics, using Bragg's diffraction law to determine the X-ray wavelengths. Moseley discovered a systematic mathematical relationship between the
wavelength In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats. It is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, t ...
s of the X-rays produced and the atomic numbers of the metals that were used as the targets in X-ray tubes. This has become known as
Moseley's law Moseley's law is an empirical law concerning the characteristic x-rays emitted by atoms. The law had been discovered and published by the English physicist Henry Moseley in 1913-1914. Until Moseley's work, "atomic number" was merely an element's ...
. Before Moseley's discovery, the atomic numbers (or elemental number) of an element had been thought of as a semi-arbitrary sequential number, based on the sequence of
atomic mass The atomic mass (''m''a or ''m'') is the mass of an atom. Although the SI unit of mass is the kilogram (symbol: kg), atomic mass is often expressed in the non-SI unit dalton (symbol: Da) – equivalently, unified atomic mass unit (u). 1&nb ...
es, but modified somewhat where chemists found this modification to be desirable, such as by the Russian chemist, Dmitri Ivanovich Mendeleev. In his invention of the Periodic Table of the Elements, Mendeleev had interchanged the orders of a few pairs of elements in order to put them in more appropriate places in this table of the elements. For example, the metals
cobalt Cobalt is a chemical element with the symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, p ...
and
nickel Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive but large pieces are slow ...
had been assigned the atomic numbers 27 and 28, respectively, based on their known chemical and physical properties, even though they have nearly the same atomic masses. In fact, the atomic mass of cobalt is slightly larger than that of nickel, which would have placed them in backwards order if they had been placed in the Periodic Table blindly according to atomic mass. Moseley's experiments in X-ray spectroscopy showed directly from their physics that cobalt and nickel have the different atomic numbers, 27 and 28, and that they are placed in the Periodic Table correctly by Moseley's objective measurements of their atomic numbers. Hence, Moseley's discovery demonstrated that the atomic numbers of elements are not just rather arbitrary numbers based on chemistry and the intuition of chemists, but rather, they have a firm experimental basis from the physics of their X-ray spectra. In addition, Moseley showed that there were gaps in the atomic number sequence at numbers 43, 61, 72, and 75. These spaces are now known, respectively, to be the places of the radioactive synthetic elements
technetium Technetium is a chemical element with the symbol Tc and atomic number 43. It is the lightest element whose isotopes are all radioactive. All available technetium is produced as a synthetic element. Naturally occurring technetium is a spontaneous ...
and promethium, and also the last two quite rare naturally occurring stable elements
hafnium Hafnium is a chemical element with the symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in many zirconium minerals. Its existence was predicted by Dmitri M ...
(discovered 1923) and
rhenium Rhenium is a chemical element with the symbol Re and atomic number 75. It is a silvery-gray, heavy, third-row transition metal in group 7 of the periodic table. With an estimated average concentration of 1 part per billion (ppb), rhenium is one ...
(discovered 1925). Nothing was known about these four elements in Moseley's lifetime, not even their very existence. Based on the intuition of a very experienced
chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe t ...
, Dmitri Mendeleev had predicted the existence of a missing element in the Periodic Table, which was later found to be filled by technetium, and
Bohuslav Brauner Bohuslav Brauner (May 8, 1855 – February 15, 1935) was a Czech chemist from the University of Prague, who investigated the properties of the rare earth elements, especially the determination of their atomic weights. Brauner predicted the ...
had predicted the existence of another missing element in this Table, which was later found to be filled by promethium. Henry Moseley's experiments confirmed these predictions, by showing exactly what the missing atomic numbers were, 43 and 61. In addition, Moseley predicted the existence of two more undiscovered elements, those with the atomic numbers 72 and 75, and gave very strong evidence that there were no other gaps in the Periodic Table between the elements
aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...
(atomic number 13) and
gold Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile me ...
(atomic number 79). This latter question about the possibility of more undiscovered ("missing") elements had been a standing problem among the chemists of the world, particularly given the existence of the large family of the lanthanide series of rare earth elements. Moseley was able to demonstrate that these lanthanide elements, i.e.
lanthanum Lanthanum is a chemical element with the symbol La and atomic number 57. It is a soft, ductile, silvery-white metal that tarnishes slowly when exposed to air. It is the eponym of the lanthanide series, a group of 15 similar elements between lant ...
through
lutetium Lutetium is a chemical element with the symbol Lu and atomic number 71. It is a silvery white metal, which resists corrosion in dry air, but not in moist air. Lutetium is the last element in the lanthanide series, and it is traditionally counted am ...
, must have exactly 15 members – no more and no less. The number of elements in the lanthanides had been a question that was very far from being settled by the chemists of the early 20th Century. They could not yet produce pure samples of all the rare-earth elements, even in the form of their
salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quant ...
s, and in some cases they were unable to distinguish between mixtures of two very similar (adjacent) rare-earth elements from the nearby pure metals in the Periodic Table. For example, there was a so-called "element" that was even given the chemical name of "
didymium Didymium ( el, , twin) is a mixture of the elements praseodymium and neodymium. It is used in safety glasses for glassblowing and blacksmithing, especially with a gas ( propane)-powered forge, where it provides a filter that selectively block ...
". "Didymium" was found some years later to be simply a mixture of two genuine rare-earth elements, and these were given the names
neodymium Neodymium is a chemical element with the symbol Nd and atomic number 60. It is the fourth member of the lanthanide series and is considered to be one of the rare-earth metals. It is a hard, slightly malleable, silvery metal that quickly tarnishe ...
and
praseodymium Praseodymium is a chemical element with the symbol Pr and the atomic number 59. It is the third member of the lanthanide series and is considered to be one of the rare-earth metals. It is a soft, silvery, malleable and ductile metal, valued for i ...
, meaning "new twin" and "green twin". Also, the method of separating the rare-earth elements by the method of
ion exchange Ion exchange is a reversible interchange of one kind of ion present in an insoluble solid with another of like charge present in a solution surrounding the solid with the reaction being used especially for softening or making water demineralised, ...
had not been invented yet in Moseley's time. Moseley's method in early X-ray spectroscopy was able to sort out the above chemical problems promptly, some of which had occupied chemists for a number of years. Moseley also predicted the existence of element 61, a lanthanide whose existence was previously unsuspected. Quite a few years later, this element 61 was created artificially in
nuclear reactor A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat fr ...
s and was named promethium.


Contribution to understanding of the atom

Before Moseley and his law, atomic numbers had been thought of as a semi-arbitrary ordering number, vaguely increasing with atomic weight but not strictly defined by it. Moseley's discovery showed that atomic numbers were not arbitrarily assigned, but rather, they have a definite physical basis. Moseley postulated that each successive element has a nuclear charge exactly one unit greater than its predecessor. Moseley redefined the idea of atomic numbers from its previous status as an ''ad hoc'' numerical tag to help sorting the elements into an exact sequence of ascending atomic numbers that made the Periodic Table exact. (This was later to be the basis of the Aufbau principle in atomic studies.) As noted by Bohr,
Moseley's law Moseley's law is an empirical law concerning the characteristic x-rays emitted by atoms. The law had been discovered and published by the English physicist Henry Moseley in 1913-1914. Until Moseley's work, "atomic number" was merely an element's ...
provided a reasonably complete experimental set of data that supported the (new from 1911) conception by
Ernest Rutherford Ernest Rutherford, 1st Baron Rutherford of Nelson, (30 August 1871 – 19 October 1937) was a New Zealand physicist who came to be known as the father of nuclear physics. ''Encyclopædia Britannica'' considers him to be the greatest ...
and
Antonius van den Broek Antonius Johannes van den Broek (4 May 1870, Zoetermeer – 25 October 1926, Bilthoven) was a Dutch amateur physicist notable for being the first who realized that the number of an element in the periodic table (now called atomic number) correspond ...
of the atom, with a positively charged nucleus surrounded by negatively charged
electron The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no ...
s in which the atomic number is understood to be the exact physical number of positive charges (later discovered and called protons) in the central atomic nuclei of the elements. Moseley mentioned the two scientists above in his research paper, but he did not actually mention Bohr, who was rather new on the scene then. Simple modifications of Rydberg's and Bohr's formulas were found to give a theoretical justification for Moseley's empirically derived law for determining atomic numbers.


Use of X-ray spectrometer

X-ray spectrometers are the foundation-stones of
X-ray crystallography X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...
. The X-ray spectrometers as Moseley knew them worked as follows. A glass-bulb electron tube was used, similar to that held by Moseley in the photo here. Inside the evacuated tube, electrons were fired at a metallic substance (i.e. a sample of pure element in Moseley's work), causing the
ionization Ionization, or Ionisation is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons, often in conjunction with other chemical changes. The resulting electrically charged atom or molecul ...
of
electron The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no ...
s from the inner
electron shell In chemistry and atomic physics, an electron shell may be thought of as an orbit followed by electrons around an atom's nucleus. The closest shell to the nucleus is called the "1 shell" (also called the "K shell"), followed by the "2 shell" (or ...
s of the element. The rebound of electrons into these holes in the inner shells next causes the emission of X-ray
photon A photon () is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force. Photons are massless, so they a ...
s that were led out of the tube in a semi-beam, through an opening in the external X-ray shielding. These are next diffracted by a standardized salt crystal, with angular results read out as photographic lines by the exposure of an X-ray film fixed at the outside the vacuum tube at a known distance. Application of
Bragg's law In physics and chemistry , Bragg's law, Wulff–Bragg's condition or Laue–Bragg interference, a special case of Laue diffraction, gives the angles for coherent scattering of waves from a crystal lattice. It encompasses the superposition of wave ...
(after some initial guesswork of the mean distances between atoms in the metallic crystal, based on its density) next allowed the wavelength of the emitted X-rays to be calculated. Moseley participated in the design and development of early X-ray spectrometry equipment, learning some techniques from
William Henry Bragg Sir William Henry Bragg (2 July 1862 – 12 March 1942) was an English physicist, chemist, mathematician, and active sportsman who uniquelyThis is still a unique accomplishment, because no other parent-child combination has yet shared a Nob ...
and
William Lawrence Bragg Sir William Lawrence Bragg, (31 March 1890 – 1 July 1971) was an Australian-born British physicist and X-ray crystallographer, discoverer (1912) of Bragg's law of X-ray diffraction, which is basic for the determination of crystal structu ...
at the
University of Leeds , mottoeng = And knowledge will be increased , established = 1831 – Leeds School of Medicine1874 – Yorkshire College of Science1884 - Yorkshire College1887 – affiliated to the federal Victoria University1904 – University of Leeds , ...
, and developing others himself. Many of the techniques of
X-ray spectroscopy X-ray spectroscopy is a general term for several spectroscopic techniques for characterization of materials by using x-ray radiation. Characteristic X-ray spectroscopy When an electron from the inner shell of an atom is excited by the energy o ...
were inspired by the methods that are used with
visible light Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 te ...
spectroscope An optical spectrometer (spectrophotometer, spectrograph or spectroscope) is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify mate ...
s and
spectrogram A spectrogram is a visual representation of the spectrum of frequencies of a signal as it varies with time. When applied to an audio signal, spectrograms are sometimes called sonographs, voiceprints, or voicegrams. When the data are represen ...
s, by substituting crystals, ionization chambers, and photographic plates for their analogs in light spectroscopy. In some cases, Moseley found it necessary to modify his equipment to detect particularly soft (lower
frequency Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as ''temporal frequency'' for clarity, and is distinct from ''angular frequency''. Frequency is measured in hertz (Hz) which is eq ...
) X-rays that could not penetrate either air or paper, by working with his instruments in a vacuum chamber.


Death and aftermath

Sometime in the first half of 1914, Moseley resigned from his position at Manchester, with plans to return to Oxford and continue his physics research there. However,
World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
broke out in August 1914, and Moseley turned down this job offer to instead enlist with the Royal Engineers of the
British Army The British Army is the principal land warfare force of the United Kingdom, a part of the British Armed Forces along with the Royal Navy and the Royal Air Force. , the British Army comprises 79,380 regular full-time personnel, 4,090 Gurk ...
. His family and friends tried to persuade him not to join, but he thought it was his duty. Moseley served as a technical officer in communications during the Battle of Gallipoli, in
Turkey Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a transcontinental country located mainly on the Anatolian Peninsula in Western Asia, with a small portion on the Balkan Peninsula in ...
, beginning in April 1915, where he was killed by a sniper on 10 August 1915. Only twenty-seven years old at the time of his death, Moseley could, in the opinion of some scientists, have contributed much to the knowledge of atomic structure had he survived.
Niels Bohr Niels Henrik David Bohr (; 7 October 1885 – 18 November 1962) was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922 ...
said in 1962 that Rutherford's work "was not taken seriously at all" and that the "great change came from Moseley." Robert Millikan wrote, "In a research which is destined to rank as one of the dozen most brilliant in conception, skillful in execution, and illuminating in results in the history of science, a young man twenty-six years old threw open the windows through which we can glimpse the sub-atomic world with a definiteness and certainty never dreamed of before. Had the European War had no other result than the snuffing out of this young life, that alone would make it one of the most hideous and most irreparable crimes in history."
George Sarton George Alfred Leon Sarton (; 31 August 1884 – 22 March 1956) was a Belgian-born American chemist and historian. He is considered the founder of the discipline of the history of science as an independent field of study. His most influential work ...
wrote, "His fame was already established on such a secure foundation that his memory will be green forever. He is one of the immortals of science, and though he would have made many other additions to our knowledge if his life had been spared, the contributions already credited to him were of such fundamental significance, that the probability of his surpassing himself was extremely small. It is very probable that however long his life, he would have been chiefly remembered because of the 'Moseley law' which he published at the age of twenty-six." Isaac Asimov wrote, "In view of what he oseleymight still have accomplished … his death might well have been the most costly single death of the War to mankind generally." Rutherford believed that Mosely's work would have earned him the Nobel Prize (which however is never awarded posthumously). Memorial plaques to Moseley were installed at Manchester and Eton, and a
Royal Society The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...
scholarship, established by his will, had as its second recipient the physicist
P. M. S. Blackett Patrick Maynard Stuart Blackett, Baron Blackett (18 November 1897 – 13 July 1974) was a British experimental physicist known for his work on cloud chambers, cosmic rays, and paleomagnetism, winning the Nobel Prize for Physics in 194 ...
, who later became president of the Society. The
Institute of Physics The Institute of Physics (IOP) is a UK-based learned society and professional body that works to advance physics education, research and application. It was founded in 1874 and has a worldwide membership of over 20,000. The IOP is the Physic ...
Henry Moseley Medal and Prize is named in his honour.


Notes


References


Further reading

*


External links

{{DEFAULTSORT:Moseley, Henry 1887 births 1915 deaths English physicists Alumni of Trinity College, Oxford People associated with the University of Manchester People from Weymouth, Dorset People educated at Eton College Royal Engineers officers British Army personnel of World War I British military personnel killed in World War I People involved with the periodic table People educated at Summer Fields School Rare earth scientists Deaths by firearm in Turkey Recipients of the Matteucci Medal Manchester Literary and Philosophical Society