Sir James Dewar FRS (20 September 1842 – 27 March 1923) was a Scottish
chemistA chemist is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties such as density and acidity. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms...
and
physicistA physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
. He is probably best-known today for his invention of the
Dewar flaskA Dewar flask is a vessel designed to provide very good thermal insulation. For instance, when filled with a hot liquid, the vessel will not allow the heat to easily escape, and the liquid will stay hot for far longer than in a typical container...
, which he used in conjunction with extensive research into the liquefaction of gases. He was also particularly interested in atomic and molecular
spectroscopySpectroscopy is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism. Later the concept was expanded greatly to comprise any interaction with radiative...
, working in these fields for more than 25 years.
Early life
James Dewar was born in Kincardine-on-Forth in 1842, the youngest of six boys. He lost his parents at the age of 15. He was educated at
Dollar AcademyDollar Academy was founded in 1818, which makes it the oldest co-educational day and boarding school in the world. The open campus occupies a site in the centre of the thriving town of Dollar in Central Scotland, less than 40 minutes drive from the two main Scottish cities, Glasgow and Edinburgh...
and the
University of EdinburghThe University of Edinburgh, founded in 1583, is a public research university located in Edinburgh, the capital of Scotland, and a UNESCO World Heritage Site. The university is deeply embedded in the fabric of the city, with many of the buildings in the historic Old Town belonging to the university...
, where he studied under
Lord PlayfairLyon Playfair, 1st Baron Playfair GCB, PC, FRS was a Scottish scientist and Liberal politician.-Background and education:...
, and later became Lord Playfair's assistant. Dewar would also study under
August KekuléFriedrich August Kekule von Stradonitz was a German organic chemist. From the 1850s until his death, Kekule was one of the most prominent chemists in Europe, especially in theoretical chemistry...
at
GhentGhent University is a Dutch-speaking public university located in Ghent, Belgium. It is one of the larger Flemish universities, consisting of 32,000 students and 7,100 staff members. The current rector is Paul Van Cauwenberge.It was established in 1817 by King William I of the Netherlands...
.
Career
In 1875, Dewar was elected Jacksonian professor of natural experimental
philosophyPhilosophy is the study of general and fundamental problems, such as those connected with existence, knowledge, values, reason, mind, and language. Philosophy is distinguished from other ways of addressing such problems by its critical, generally systematic approach and its reliance on rational...
at the
University of CambridgeThe University of Cambridge is a public research university located in Cambridge, United Kingdom. It is the second-oldest university in both the United Kingdom and the English-speaking world , and the seventh-oldest globally...
, becoming a fellow of
PeterhousePeterhouse is a constituent college of the University of Cambridge, England. It is the oldest college of the University, having been founded in 1284 by Hugo de Balsham, Bishop of Ely...
. He became a member of the
Royal InstitutionThe Royal Institution of Great Britain is an organization devoted to scientific education and research, based in London.-Overview:...
and later, replaced Dr.
John Hall GladstoneJohn Hall Gladstone FRS was a British chemist. He served as President of the Physical Society between 1874 and 1876 and during 1877–1879 was President of the Chemical Society...
in the role of Fullerian Professor of Chemistry in 1877. Dewar was also the President of the
Chemical SocietyThe Chemical Society was formed in 1841 as a result of increased interest in scientific matters....
in 1897 and the
British Association for the Advancement of Scienceframe|right|"The BA" logoThe British Association for the Advancement of Science or the British Science Association, formerly known as the BA, is a learned society with the object of promoting science, directing general attention to scientific matters, and facilitating interaction between...
in 1902, as well as serving on the
Royal CommissionIn Commonwealth realms and other monarchies a Royal Commission is a major ad-hoc formal public inquiry into a defined issue. They have been held in various countries such as the United Kingdom, Australia, Canada, New Zealand, and Saudi Arabia...
established to examine London's water supply from 1893 to 1894 and the Committee on Explosives. It was whilst he was serving on the Committee on Explosives that he and Frederick Augustus Abel developed
corditeCordite is a family of smokeless propellants developed and produced in the United Kingdom from 1889 to replace gunpowder as a military propellant. Like gunpowder, cordite is classified as a low explosive because of its slow burning rates and consequently low brisance...
, a smokeless gunpowder alternative.
In 1867 Dewar described several chemical formulae for
benzeneBenzene is an organic chemical compound. It is composed of 6 carbon atoms in a ring, with 1 hydrogen atom attached to each carbon atom, with the molecular formula C6H6....
. Ironically, one of the formulae, which does not represent benzene correctly and was not advocated by Dewar, is sometimes still called
Dewar benzeneDewar benzene or bicyclo[2.2.0]hexa-2,5-diene is a bicyclic isomer of benzene with the molecular formula C6H6. The compound is named after James Dewar who included this structure in a list of possible C6H6 structures in 1867....
.
His scientific work covers a wide field - his earlier paper cover a wide range of topics;
organic chemistryOrganic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation of carbon-based compounds, hydrocarbons, and their derivatives...
,
HydrogenHydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
and its physical constants, high temperature research, the temperature of the sun and of the
electric sparkAn electric spark is a type of electrostatic discharge that occurs when an electric field creates an ionized electrically conductive channel in air producing a brief emission of light and sound. A spark is formed when the electric field strength exceeds the dielectric field strength of air...
, electro-photometry and the chemistry of the
electric arcAn electric arc is an electrical breakdown of a gas which produces an ongoing plasma discharge, resulting from a current flowing through normally nonconductive media such as air. A synonym is arc discharge. An arc discharge is characterized by a lower voltage than a glow discharge, and relies on...
.
With Professor J. G. McKendrick, of Glasgow, he investigated the physiological action of light, and examined the changes which take place in the electrical condition of the
retinaThe vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
under its influence. With Professor G. D. Living, one of his colleagues at Cambridge, he began in 1878 a long series of
spectroscopicSpectroscopy is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism. Later the concept was expanded greatly to comprise any interaction with radiative...
observations, the later of which were devoted to the spectroscopic examination of various gaseous elements separated from atmospheric air by the aid of low temperatures; and he was joined by Professor J. A. Fleming, of
University College LondonUniversity College London is a public research university located in London, United Kingdom and the oldest and largest constituent college of the federal University of London...
, in the investigation of the electrical behaviour of substances cooled to very low temperatures.
His name is most widely known in connection with his work on the
liquefactionLiquefaction may refer to:* Liquefaction, the general process of becoming liquid* Soil liquefaction, the process by which sediments become suspended* Liquefaction of gases in physics, chemistry, and thermal engineering* Liquefactive necrosis in pathology...
of the so-called permanent gases and his researches at temperatures approaching
absolute zeroAbsolute zero is the theoretical temperature at which entropy reaches its minimum value. The laws of thermodynamics state that absolute zero cannot be reached using only thermodynamic means....
. His interest in this branch of physics and chemistry dates back at least as far as 1874, when he discussed the "Latent Heat of Liquid Gases" before the British Association. In 1878 he devoted a Friday evening lecture at the
Royal InstitutionThe Royal Institution of Great Britain is an organization devoted to scientific education and research, based in London.-Overview:...
to the then recent work of
Louis Paul CailletetLouis-Paul Cailletet was a French physicist and inventor.- Life and work :Cailletet was born in Châtillon-sur-Seine, Côte-d'Or. Educated in Paris, Cailletet returned to Châtillon to manage his father's ironworks...
and
Raoul PictetRaoul-Pierre Pictet was a Swiss physicist and the first person to liquefy nitrogen. He was born in Geneva and served as professor in the university of that city...
, and exhibited for the first time in Great Britain the working of the Cailletet apparatus. Six years later, again at the Royal Institution, he described the researches of
Zygmunt Florenty WróblewskiZygmunt Florenty Wróblewski was a Polish physicist and chemist.-Life:Wróblewski was born in Grodno . He studied at Kiev University. After a six-year exile for participating in the January 1863 Uprising against Imperial Russia, he studied in Berlin and Heidelberg...
and
Karol OlszewskiKarol Stanisław Olszewski was a Polish chemist, mathematician and physicist.-Life:Olszewski was a graduate of Kazimierz Brodziński High School in Tarnów . He studied at Kraków's Jagiellonian University in the departments of mathematics and physics, and chemistry and biology...
, and illustrated for the first time in public the
liquefactionLiquefaction of gases includes a number of phases used to convert a gas into a liquid state. The processes are used for scientific, industrial and commercial purposes. Many gases can be put into a liquid state at normal atmospheric pressure by simple cooling; a few, such as carbon dioxide, require...
of
oxygenOxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
and air. Soon afterwards he built a machine from which the liquefied gas could be drawn off through a valve for use as a cooling agent, before using the liquid oxygen in research work related to meteorites; about the same time he also obtained oxygen in the solid state.
By 1891 he had designed and built, at the Royal Institution, machinery which yielded liquid oxygen in industrial quantities, and towards the end of that year he showed that both liquid oxygen and liquid ozone are strongly attracted by a magnet. About 1892 the idea occurred to him of using vacuum-jacketed vessels for the storage of liquid gases - the Dewar flask (otherwise known as a Thermos or
vacuum flaskA vacuum flask is an insulating storage vessel which keeps its contents hotter or cooler than its surroundings. Invented by Sir James Dewar in 1892, the vacuum flask consists of two flasks, placed one within the other and joined at the neck...
) - the invention for which he became most famous. The vacuum flask was so efficient at keeping heat out that it was found possible to preserve the liquids for comparatively long periods, making examination of their optical properties possible. Dewar did not profit from the widespread adoption of his vacuum flask - he lost a court case against
ThermosThermos L.L.C. is the leading manufacturer worldwide of insulated food and beverage containers and other consumer products. The company was founded in 1904.-Thermos as a trademark:...
concerning the patent for his invention. While Dewar was recognised as the inventor, because he did not patent his invention there was no way to stop Thermos from using the design.
He next experimented with a high pressure hydrogen jet by which low temperatures were realized through the
Joule–Thomson effectIn thermodynamics, the Joule–Thomson effect or Joule–Kelvin effect or Kelvin–Joule effect describes the temperature change of a gas or liquid when it is forced through a valve or porous plug while kept insulated so that no heat is exchanged with the environment. This procedure is called a...
, and the successful results he obtained led him to build at the Royal Institution a large
regenerative coolingRegenerative cooling in rockets is where some or all of the propellant is passed through tubes, channels or otherwise in a jacket around the combustion chamber or nozzle to cool the engine because the fuel in particular and sometimes the oxidizer are good coolants...
refrigerating machine. Using this machine in 1898,
liquid hydrogenLiquid hydrogen is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.To exist as a liquid, H2 must be pressurized above and cooled below hydrogen's Critical point. However, for hydrogen to be in a full liquid state without boiling off, it needs to be...
was collected for the first time, solid
hydrogenHydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
following in 1899. He tried to liquefy the last remaining gas,
HeliumHelium is the chemical element with atomic number 2 and an atomic weight of 4.002602, which is represented by the symbol He. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas that heads the noble gas group in the periodic table...
, which condenses into a liquid at −268.9°C, but owing to a number of factors, including a lack of Helium with which to work, Dewar was preceded by
Heike Kamerlingh OnnesHeike Kamerlingh Onnes was a Dutch physicist and Nobel laureate. He pioneered refrigeration techniques, and he explored how materials behaved when cooled to nearly absolute zero. He was the first to liquify helium...
as the first person to produce
liquid heliumHelium exists in liquid form only at extremely low temperatures. The boiling point and critical point depend on the isotope of the helium; see the table below for values. The density of liquid helium-4 at its boiling point and 1 atmosphere is approximately 0.125 g/mL Helium-4 was first liquefied...
, in 1908. Onnes would later be awarded the
Nobel Prize in PhysicsThe Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...
for his research into the properties of matter at low temperatures - Dewar was nominated several times but never successful in winning the Nobel Prize.
In 1905 he began to investigate the gas-absorbing powers of
charcoalCharcoal is the dark grey residue consisting of carbon, and any remaining ash, obtained by removing water and other volatile constituents from animal and vegetation substances. Charcoal is usually produced by slow pyrolysis, the heating of wood or other substances in the absence of oxygen...
when cooled to low temperatures, and applied his research to the production of high vacuums, which were useful for further experiments in atomic physics. Dewar would continue his research work into the properties of elements at low temperatures, specifically low-temperature
calorimetryCalorimetry is the science of measuring the heat of chemical reactions or physical changes. Calorimetry is performed with a calorimeter. The word calorimetry is derived from the Latin word calor, meaning heat...
, until the outbreak of
World War IWorld War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
. The Royal Institution laboratories lost a number of staff to the war effort, both in fighting and scientific roles, and after the war, Dewar had little interest in re-starting the serious research work which went on before the War. Shortages of scholars necessarily compounded the problems. His research during and after the war mainly involved investigating
surface tensionSurface tension is a property of the surface of a liquid that allows it to resist an external force. It is revealed, for example, in floating of some objects on the surface of water, even though they are denser than water, and in the ability of some insects to run on the water surface...
in soap bubbles, rather than further work into the properties of matter at low temperatures.
Honours and Awards
Whilst Dewar was never recognised by the
Swedish AcademyThe Swedish Academy , founded in 1786 by King Gustav III, is one of the Royal Academies of Sweden.-History:The Swedish Academy was founded in 1786 by King Gustav III. Modelled after the Académie française, it has 18 members. The motto of the Academy is "Talent and Taste"...
, he was recognised by many other institutions both before and after his death, both in Britain and overseas. The Royal Society elected him a Fellow of the Royal Society in June 1877 and bestowed their
RumfordThe Rumford Medal is awarded by the Royal Society every alternating year for "an outstandingly important recent discovery in the field of thermal or optical properties of matter made by a scientist working in Europe". First awarded in 1800, it was created after a 1796 donation of $5000 by the...
(1894),
DavyThe Davy Medal is awarded by the Royal Society of London "for an outstandingly important recent discovery in any branch of chemistry". Named after Humphry Davy, the medal is awarded with a gift of £1000. The medal was first awarded in 1877 to Robert Wilhelm Bunsen and Gustav Robert Kirchhoff "for...
(1909), and
Copley MedalThe Copley Medal is an award given by the Royal Society of London for "outstanding achievements in research in any branch of science, and alternates between the physical sciences and the biological sciences"...
(1916) medals upon him for his work, as well as inviting him to deliver their
Bakerian LectureThe Bakerian Lecture is a prize lecture of the Royal Society, a lecture on physical sciences.In 1775 Henry Baker left £100 for a spoken lecture by a Fellow on such part of natural history or experimental philosophy as the Society shall determine....
in 1901. In 1899 he became the first recipient of the Hodgkins gold medal of the
Smithsonian InstitutionThe Smithsonian Institution is an educational and research institute and associated museum complex, administered and funded by the government of the United States and by funds from its endowment, contributions, and profits from its retail operations, concessions, licensing activities, and magazines...
,
Washington, D.C.Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....
, for his contributions to our knowledge of the nature and properties of atmospheric air.
In 1904 he was the first British subject to receive the
Lavoisier medalA Lavoisier Medal is an award made by any of a number of bodies, for achievements in chemical related disciplines. The award is named for Antoine Lavoisier, considered by some to be a father of modern chemistry....
of the French Academy of Sciences, and in 1906 he was the first to be awarded the
Matteucci medalThe Matteucci Medal was established to award physicists for their fundamental contributions. Under an Italian Royal Decree dated July 10, 1870, the Italian Society of Sciences was authorized to receive a donation from Carlo Matteucci for the establishment of the Prize.Matteucci Medalists* 1868...
of the Italian Society of Sciences. He was knighted in 1904 and awarded the Gunning Victoria Jubilee Prize for 1900-1904 by the
Royal Society of EdinburghThe Royal Society of Edinburgh is Scotland's national academy of science and letters. It is a registered charity, operating on a wholly independent and non-party-political basis and providing public benefit throughout Scotland...
, and in 1908 he was awarded the Albert medal of
The Society of ArtsThe Royal Society for the encouragement of Arts, Manufacturers and Commerce is a British multi-disciplinary institution, based in London. The name Royal Society of Arts is frequently used for brevity...
. A
lunar craterDewar is a lunar crater that lies on the Moon's far side. Less than one crater diameter to the south-southwest is the crater Stratton. Vening Meinesz is a little over one crater diameter to the northwest. The slightly worn rim of this crater is roughly circular, with a small outward protrusion...
has been named in his honor.
James Dewar died in London in 1923, still holding the office of Fullerian Professor of Chemistry at the Royal Institution, having refused to retire. He was cremated at the
Golders Green CrematoriumGolders Green Crematorium and Mausoleum was the first crematorium to be opened in London, and one of the oldest crematoria in Britain. The land for the crematorium was purchased in 1900, costing £6,000, and was opened in 1902 by Sir Henry Thompson....
where his ashes remain.
Further reading
,
Liquid Air and the Liquefaction of Gases, Norman W. Henley and Co., New York, 1900, second edition (extensive description of Dewar's work on the liqufaction of gases)
External links