C. T. R. Wilson

Charles Thomson Rees Wilson (14 February 1869 – 15 November 1959) was a British meteorologist and physicist who shared the 1927 Nobel Prize in Physics with Arthur Compton for his invention of the cloud chamber.<ref name=Nobel1927>Template:Cite web</ref>

Early life and education

Charles Thomson Rees Wilson was born on 14 February 1869 in Glencorse, Scotland, the son of John Wilson, a sheep farmer, and Annie Clark Harper. After his father died in 1873, he moved with his family to Manchester, England.<ref name=NobelBio>Template:Cite web</ref>

With financial support from his step-brother, Wilson studied biology at Owens College (now the University of Manchester) with the intent of becoming a doctor. He graduated with a B.Sc. in 1887. He then won a scholarship to attend Sidney Sussex College, Cambridge, where he became interested in physics and chemistry. In 1892, he received First Class Honours in both parts of the Natural Science Tripos.<ref name="ODNB">Template:Cite ODNB</ref><ref>Template:Acad</ref><ref name=NobelBio/>

Career and research

Wilson became particularly interested in meteorology, and in 1893 he began to study clouds and their properties. Beginning in 1894, he worked for some time at the observatory on Ben Nevis,<ref name="Origin and context">Template:Cite journal</ref> where he made observations of cloud formation. He was particularly fascinated by the appearance of glories.<ref name="Brocklehurst">Template:Cite news</ref> He then tried to reproduce this effect on a smaller scale in the Cavendish Laboratory at Cambridge, expanding humid air within a sealed container.

In 1895, Wilson discovered that at a large enough expansion, ratio supersaturated water vapour condensates even without dust which he removed by previous condensations, contrary to the previous research by John Aitken.<ref>Template:Cite book</ref> Under J. J. Thomson's mentorship by 1896, he found out that X-rays stimulate the condensation just as well as dust.<ref>Template:Cite journal</ref>

In 1900, Wilson became a Fellow of Sidney Sussex College, Cambridge, and was appointed University Lecturer and Demonstrator.<ref name=NobelBio/> He was known by some as a poor lecturer, due to a pronounced stutter.<ref name="Halliday">Template:Cite journal</ref> He taught a course on atmospheric electricity as a visiting lecturer at Imperial College London.<ref>Template:Cite journal</ref> He was appointed Reader in Electrical Meteorology in 1918 and Jacksonian Professor in 1925.<ref name=NobelBio/>

In 1906, Wilson hypothesised that cosmic radiation generates the ions causing condensation without apparent reasons.<ref>Template:Cite journal</ref>

Wilson published numerous papers on meteorology and physics, on topics including X-rays,<ref name="Investigations">Template:Cite journal</ref> ionisation,<ref name="Making Visible">Template:Cite journal</ref> thundercloud formation,<ref name="Theory of Thundercloud">Template:Cite journal</ref> and other meteorological events.<ref name="Brocklehurst" /> Wilson may also have observed a sprite in 1924, 65 years before their official discovery.<ref name="Bowler">Template:Cite web</ref> Weather was a focus of his work throughout his career, from his early observations at Ben Nevis to his final paper, on thunderclouds.<ref>Template:Cite journal</ref><ref name="Theory of Thundercloud"/>

Cloud chamber

Wilson's original cloud chamber

The invention of the cloud chamber was by far Wilson's signature accomplishment, earning him the Nobel Prize in Physics in 1927.<ref>Template:Cite journal</ref> The Cavendish Laboratory praised him for the creation of "a novel and striking method of investigating the properties of ionised gases."<ref name="Collotype">Template:Cite book</ref> The cloud chamber allowed huge experimental leaps forward in the study of subatomic particles and the field of particle physics, generally. Some have credited Wilson with making the study of particles possible at all.<ref name="Brocklehurst" />

Commemorative plaque at Ben Nevis about the observatory there, and Wilson's cloud chamber

Wilson later experimented with the creation of cloud trails in his chamber by condensation onto ions generated by radioactivity. Several of his cloud chambers survive.<ref>Template:Cite journal</ref>

Retrospectively, Wilson's experimental method has received some attention from scholars.

In a period of scientific inquiry characterised by a divide between "analytical" and "morphological" scientists, Wilson's method of inquiry represented a hybrid. While some scientists believed phenomena should be observed in pure nature, others proposed laboratory-controlled experiments as the premier method for inquiry. Wilson used a combination of methods in his experiments and investigations.<ref name="Gooding">Template:Cite book</ref> Wilson's work "made things visible whose properties had only previously been deduced indirectly."<ref name="Brocklehurst" />

Wilson has been called "almost the last of the great individual experimenters in physics."<ref name="Halliday" /> He used his cloud chamber in various ways to demonstrate the operating principles of things like subatomic particles and X-rays.<ref name="Investigations" /><ref name="Making Visible" /> But his primary interest, and the subject of the bulk of his papers, was meteorology.<ref name="Gooding" />

Personal life and death

In 1908, Wilson married Jessie Fraser, the daughter of a minister from Glasgow. They had four children. His family knew him as patient and curious, and fond of taking walks in the hills near his home.<ref name="Bowler" />

Wilson died on 15 November 1959 at his home in Carlops at the age of 90, surrounded by his family.<ref name="ODNB" />

Recognition

Memberships

Country	Year	Institute	Type	Template:Reference column heading
Template:Flagdeco United Kingdom	1900	Royal Society	Fellow	<ref>Template:Cite web</ref>

Awards

Country	Year	Institute	Award	Citation	Template:Reference column heading
Template:Flagdeco United Kingdom	1911	Royal Society	Hughes Medal	"For his work on nuclei in dust-free air, and his work on ions in gases and atmospheric electricity"	<ref>Template:Cite web</ref>
Template:Flag	1922	Royal Society	Royal Medal	"For his researches on condensation nuclei and atmospheric electricity"	<ref>Template:Cite web</ref>
Template:Flag	1925	Franklin Institute	Howard N. Potts Medal	"Method of making the tracks of ionising rays visible and permanently recording them by photography"	<ref>Template:Cite web</ref>
Template:Flag	1927	Royal Swedish Academy of Sciences	Nobel Prize in Physics	"For his method of making the paths of electrically charged particles visible by condensation of vapour"	<ref name=Nobel1927/>
Template:Flag	1929	Franklin Institute	Franklin Medal	"Pioneer contributions to atomic physics and to our knowledge of atomic structure"	<ref>Template:Cite web</ref>
Template:Flag	1931	Institute of Physics	Duddell Medal and Prize		<ref>Template:Cite web</ref>
Template:Flag	1935	Royal Society	Copley Medal	"For his work on the use of clouds in advancing our knowledge of atoms and their properties"	<ref>Template:Cite web</ref>

Chivalric orders

Country	Year	Monarch	Order	Citation	Template:Reference column heading
Template:Flag	1937	George VI	Order of the Companions of Honour	"For services to experimental physics"	<ref>Template:London Gazette</ref>

Commemorations

The Wilson crater on the Moon is named after him, Alexander Wilson, and Ralph Elmer Wilson.<ref>Template:Cite web</ref> The Wilson Condensation Cloud formations that occur after large explosions, such as nuclear detonations, are named after him.<ref>Template:Cite book</ref> The Wilson Society—the scientific society of Sidney Sussex College, Cambridge—is named in his honour,<ref>Template:Cite web</ref> as is the CTR Wilson Institute for Atmospheric Electricity—the Atmospheric Electricity Special Interest Group of the Royal Meteorological Society.<ref>CTR Wilson Institute for Atmospheric Electricity</ref>

The archives of C.T.R. Wilson are maintained by the Archives of the University of Glasgow.<ref>Template:Cite web</ref>

in 1996, a blue plaque in Wilson's honour was installed in a specially built cairn at Flotterstone, close to his birthplace at Crosshouse Farm.<ref>Template:Cite web</ref>

In 2012, the Royal Society of Edinburgh held a meeting in honour of Wilson, the "Great Scottish Physicist."<ref name="Aplin">Template:Cite journal</ref>

External links

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• The Papers of C. T. R. Wilson held at Churchill Archives Centre