George Johnstone Stoney

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George Johnstone Stoney

George Johnstone Stoney (born February 15, 1826 in Oakley Park, County Offaly , Ireland , † July 5, 1911 in London ) was an Irish physicist . He gave the elementary charge the name electron .

life and work

Stoney attended Trinity College Dublin in the Irish capital and was then assistant professor at the observatory of William Parsons, 3rd Earl of Rosse in Birr Castle . Later he was Professor of Physics (Natural Philosophy) at Queens College in Galway ( National University of Ireland, Galway ) and was then at Queens University in Dublin, where he was Secretary of the Administrative Center of the Queen's Colleges.

In 1874, Stoney proposed the existence of electrical charge carriers of uniform charge that should be associated with the atoms. From the electrolysis, he derived initial estimates of its charge , but it was a factor of 20 too low. He made the first suggestions for this at the meeting of the British Association in Belfast in 1874 ( On the physical units of Nature , published only in 1881) and then in 1891 in the Trans. Royal Dublin Society (Volume 4, p. 583), where he also used the name Electron suggested. One possible reason for choosing the name was that electron is the Greek word for amber , the material on which electrostatic phenomena had been observed for the first time. In his work from 1874 he made the first proposal for a system of measurements of natural units , which he based on the electron charge , the gravitational constant and the speed of light as natural constants.

The electron was first detected as an elementary particle in 1897 by Joseph John Thomson (he called it corpuscle ), its electrical charge was determined in 1907 by Robert Millikan . The electron charge, also known as the elementary charge as the smallest free quantum of charge , is 1.602 · 10 −19 C ( Coulomb ).

Stony's determination of the elementary charge was related to his attempts to determine the Avogadro constant (or the Faraday constant ) (as did Johann Josef Loschmidt and William Thomson, 1st Baron Kelvin ).

Stoney also dealt with spectroscopy. He was looking for a splitting of the spectral lines in the magnetic field, but this could only be demonstrated by Pieter Zeeman in 1896 , and he anticipated some of the laws that Johann Jakob Balmer found in the hydrogen spectrum in 1885 ( Balmer series ). He also designed a heliostat .

Stony's family

George Stony's younger brother Bindon Blood Stoney (1828-1909) was an engineer who also made contributions to astronomy. George Stony's nephew, George Francis FitzGerald, was a physicist. George Stoney had five children. His eldest, his son George Gerald Stoney (1863–1942), was also an engineer; He became a professor of mechanical engineering in Manchester in 1917 and is best known today for the equation named after him. George Stony's daughters, the physicist Edith Anne Stoney (1869–1938) and the physician Florence Ada Stoney (1870–1932) pioneered the field of X-ray radiology - Florence was Great Britain's first female radiologist.


  • G. O'Hara: George Johnstone FRS and the Concept of the Electron . Notes and Records of the Royal Society, 29 (2), 265-276, 1975.
  • the same: George Johnstone Stoney and the Conceptual Discovery of the Electron . Occasional Papers in Science and Technology Eight: Stoney and the Electron, Royal Dublin Society, 5-28, 1993.
  • Alex Keller: The Infancy of Atomic Physics. Hercules in His Cradle , Oxford University, 1983, ISBN 0-19-853904-5 .

Web links

Individual evidence

  1. Abraham Pais Inward Bound , p. 74
  2. ^ Philosophical Magazine, Volume 11, 1881, p. 381
  3. ^ Electron . In: Encyclopædia Britannica . 11th edition. tape 9 : Edwardes - Evangelical Association . London 1910, p. 237 (English, full text [ Wikisource ]).
  4. George Gerald Stoney. In: Grace's Guide to British Industrial History. Grace's Guide Ltd., accessed December 15, 2019 .
  5. Arthur Andrews, Chris Jackson: The Stoneys of Heaton: unsung heroes of the Parsons' story. In: Heaton History Group. Heaton History Group, April 7, 2018, accessed December 15, 2019 .
  6. JE Greene: Review Article: Tracing the recorded history of thin-film sputter deposition: From the 1800s to 2017 . In: AIP (ed.): Journal of Vacuum Science & Technology A . tape 35 , no. 5 . AIP Publishing, September 1, 2017, ISSN  0734-2101 , p. 05C204 , doi : 10.1116 / 1.4998940 ( ).
  7. ^ Francis Duck: Edith and Florence Stoney, X-ray pioneers . In: Bristol Medico-Chirurgical Society (Ed.): The West of England Medical Journal . tape 115 , no. 1 , March 2016, p. Article 2 ( [PDF]).