Sir Charles Drummond Ellis
(b.
Hampstead, 11 August 1895; died
Cookham
Cookham is a historic River Thames, Thames-side village and civil parishes in England, civil parish on the north-eastern edge of Berkshire, England, north-north-east of Maidenhead and opposite the village of Bourne End, Buckinghamshire, Bourne ...
10 January 1980) 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 ...
and scientific administrator. His work on the magnetic spectrum of the beta-rays helped to develop a better understanding of nuclear structure.
Education and internment
Ellis was the son of Abraham Charles Ellis, a general manager of the
Metropolitan Railway, and Isabelle Flockart Carswell. He won a scholarship to
Harrow School where he excelled academically as well as at sport. In 1913 he became a
cadet in the
Royal Military Academy in preparation for a career in the
Royal Engineers.
He was holidaying in Germany the following summer 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. All British nationals were rounded up and sent to the
Ruhleben internment camp
Ruhleben internment camp was a civilian detention camp in Germany during World War I. It was located in Ruhleben, a former ''Vorwerk'' manor to the west of Berlin, now split between the districts of Spandau and Charlottenburg-Wilmersdorf. The ...
just outside Berlin. The camp had been a horse racecourse. During internment the detainees had a large degree of freedom. They had access to books, and Ellis made good use of his time to study. Another detainee in the camp was
James Chadwick
Sir James Chadwick, (20 October 1891 – 24 July 1974) was an English physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932. In 1941, he wrote the final draft of the MAUD Report, which inspi ...
who was later to receive the
Nobel Prize
The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...
for his work on the discovery of the
neutron
The neutron is a subatomic particle, symbol or , which has a neutral (not positive or negative) charge, and a mass slightly greater than that of a proton. Protons and neutrons constitute the nuclei of atoms. Since protons and neutrons beh ...
. Chadwick inspired Ellis and together they erected a laboratory in one of the horse stables where they undertook scientific experiments on the
photochemical
Photochemistry is the branch of chemistry concerned with the chemical effects of light. Generally, this term is used to describe a chemical reaction caused by absorption of ultraviolet (wavelength from 100 to 400 nm), visible light (400–7 ...
process.
Career after the war
After the war Ellis decided to abandon a military career. He entered
Trinity College, Cambridge
Trinity College is a constituent college of the University of Cambridge. Founded in 1546 by King Henry VIII, Trinity is one of the largest Cambridge colleges, with the largest financial endowment of any college at either Cambridge or Oxford. ...
where he studied
natural sciences
Natural science is one of the branches of science concerned with the description, understanding and prediction of natural phenomena, based on empirical evidence from observation and experimentation. Mechanisms such as peer review and repeatab ...
. After graduating in 1920 he became engaged in research work at the
Cavendish Laboratory,
Cambridge
Cambridge ( ) is a College town, university city and the county town in Cambridgeshire, England. It is located on the River Cam approximately north of London. As of the 2021 United Kingdom census, the population of Cambridge was 145,700. Cam ...
, where the director, Sir
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 ...
, had now engaged Chadwick. While Rutherford and Chadwick worked on alpha
radioactivity and alpha particles for nuclear disintegration experiments Ellis studied beta and gamma radiation. He became a leading authority on the subject, publishing many articles in scientific journals.
In 1921 Ellis had become a fellow of Trinity College and was appointed assistant lecturer in natural science. In 1925 he married Paula Warzcewska, the daughter of a wealthy Polish
shipbuilder
Shipbuilding is the construction of ships and other floating vessels. It normally takes place in a specialized facility known as a shipyard. Shipbuilders, also called shipwrights, follow a specialized occupation that traces its roots to befor ...
. Although there were no children Paula (known as Polly in England) had a daughter from a previous marriage. In 1929 he was elected a fellow of the
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 ...
.
In 1930 Rutherford, Chadwick and Ellis published together a classic monograph ''Radiations from Radioactive Substances''.
Discovery of the neutrino
During the early 1930s Ellis worked with
Nevill Mott
Sir Nevill Francis Mott (30 September 1905 – 8 August 1996) was a British physicist who won the Nobel Prize for Physics in 1977 for his work on the electronic structure of magnetic and disordered systems, especially amorphous semiconductors. ...
on energy relations in
beta decay
In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which a beta particle (fast energetic electron or positron) is emitted from an atomic nucleus, transforming the original nuclide to an isobar of that nuclide. For ...
. Mott said later that Ellis had “practically discovered the
neutrino
A neutrino ( ; denoted by the Greek letter ) is a fermion (an elementary particle with spin of ) that interacts only via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass ...
”. He worked with W.J. Henderson on the energy distribution of
positrons in artificial radioactivity. In 1936 Ellis was elected a fellow of the
American Physical Society. In 1936, a year after Chadwick’s appointment to a professorship at
Liverpool
Liverpool is a city and metropolitan borough in Merseyside, England. With a population of in 2019, it is the 10th largest English district by population and its metropolitan area is the fifth largest in the United Kingdom, with a populat ...
, Ellis was appointed to the Wheatstone chair of physics at
King's College London in succession to
Edward Victor Appleton who had become professor of natural sciences at Cambridge. Ellis continued his research alongside his new teaching and administration commitments.
In 1940 Ellis became a member of
MAUD who were investigating the possibility of using nuclear fission to develop new weapons. He became scientific adviser to the army council from 1943–1946, serving on several high-level committees. He was
knight
A knight is a person granted an honorary title of knighthood by a head of state (including the Pope) or representative for service to the monarch, the church or the country, especially in a military capacity. Knighthood finds origins in the Gr ...
ed in 1946 for his war service.
Later career
After World War II Ellis held several posts which were not related to nuclear weapons. He was director of the Finance Corporation for Industry, in charge of research and development for the
National Coal Board
The National Coal Board (NCB) was the statutory corporation created to run the nationalised coal mining industry in the United Kingdom. Set up under the Coal Industry Nationalisation Act 1946, it took over the United Kingdom's collieries on "ve ...
. He was president of the British Coal Utilization Research Association from 1946–1955 and a member of the advisory council to the minister of fuel and power from 1947 to 1955. He became scientific adviser to the
British American Tobacco Company (BAT) at a time when the association between
smoking and various diseases was just starting to be suspected. He retired from the Gas Council in 1966 and from BAT in 1972.
During his final decade his health was poor. In 1980 he died in a nursing home in Cookham after a short illness.
Ellis–Wooster experiment
In 1927 Ellis and William Alfred Wooster (1903–1984) performed an important experiment with β-rays. Their experiment led to Pauli's suggestion of the neutrino.
References
Further reading
The Ruhleben Story
{{DEFAULTSORT:Ellis, Charles Drummond
1895 births
1980 deaths
English physicists
People from Hampstead
People educated at Harrow School
Academics of King's College London
Alumni of Trinity College, Cambridge
Experimental physicists
Fellows of the Royal Society
Fellows of the American Physical Society
Knights Bachelor
World War I civilian detainees held by Germany