- James Alfred Ewing
name = James Alfred Ewing
caption = James Alfred Ewing
27 March 1855
7 January 1935
nationality = Scottish
Sir James Alfred Ewing KCB (
27 March 1855- 7 January 1935) was a Scottish physicistand engineer, best known for his work on the magnetic properties of metals and, in particular, for his discovery of, and coinage of the word, " hysteresis".
(Note: According to the book "Sir Alfred Ewing: A Pioneer in Physics and Engineering" (1946) by Professor Bates, the discovery of magnetic hysteresis probably occurred before Ewing. However, Ewing re-discovered it, studied it in detail and coined the word "
hysteresis". Please see reference below.)
Dundee, Scotland, the third son of a minister of the Free Church of Scotland and educated at West End Academy and the High School of Dundee, Ewing showed an early interest in scienceand technology.
Ewing graduated in
engineeringfrom the University of Edinburghwhere he studied under William Thomson, 1st Baron Kelvinand Peter Guthrie Tait. During his summer vacations, he worked on telegraphcable laying expeditions, including one to Brazil, under Thomson and Fleeming Jenkin.
In 1878, on Fleeming Jenkin's recommendation, Ewing was recruited to help the modernisation of
Meiji Era Japanas one of the " o-yatoi gaikokujin" (hired foreigners). Serving as professor of mechanical engineeringat the University of Tokyo, he was instrumental in founding Japanese seismology.
Ewing made two special friends at Tokyo University soon after arriving:
Basil Hall Chamberlainand Lieutenant Thomas Henry JamesR.N. who taught navigation. He was also in close contact with Henry Dyerand William Edward Ayrtonat the Imperial College of Engineering(Kobu Dai Gakko).
In Tokyo, Ewing taught courses in mechanics and on heat engines to engineering students, and electricity and magnetism to students of physics. He carried out many research projects on magnetism and coined the word 'hysteresis'. His investigations into earthquakes led him to help T. Lomar Gray and
John Milneof the Imperial College of Engineering to develop a seismometer. All three men worked as a team on the invention and use of seismographs, though Milne is generally credited with the invention of the first modern horizontal-pendulum seismograph.
In 1883, Ewing returned to Scotland to work at the University College Dundee where he was appalled by the living conditions of many of the poorer areas of the town which he felt compared unfavourably with those in Japan. He worked fervently with local government and industry to improve amenities, in particular
sewersystems, and to lower the infant mortality rate.
University of Cambridge
In 1890, he took up the post of professor of mechanism and applied mechanics at
King's College, Cambridge. At Cambridge, Ewing's research into the magnetisation of metals led him to criticise the conventional account of Wilhelm Weber. In 1890, he observed that magnetisation lagged behind an applied alternating current. He described the characteristic hysteresis curve and speculated that individual molecules act as magnets, resisting changes in magnetising potential. Ewing was a close friend of Sir Charles Algernon Parsonsand collaborated with him on the development of the steam turbine, participating in the sea-trials of the " Turbinia". He also researched into the crystalline structure of metals and, in 1903, was the first to propose that fatigue failures originated in microscopic defects or "slip bands" in materials.
University of Edinburgh
In 1903, he became director of naval education at the
Admiraltybefore becoming principal and vice-chancellor of the University of Edinburghin 1916, a post he held until his retirement in 1929. From 1914 to May 1917, he managed " Room 40", the admiralty intelligence department of cryptanalysis, responsible predominantly for the decryption of intercepted German naval messages. In this capacity, he achieved some notoriety in the popular press when Room 40 deciphered the Zimmermann Telegramin 1917 (which suggested a German plot to assist Mexicoin annexing the southwestern United States).
In May 1916 Ewing accepted an invitation to become Vice-Chancellor of Edinburgh University, in the course of which he instituted an extensive series of effective reforms.
Knighted in 1911, Sir James Alfred Ewing retired from Edinburgh University in 1929 and died in 1935.
*Fellow of the
Royal Society of Edinburgh(1878);
*Fellow of the
*President of the Royal Society of Edinburgh (1924 - 1929);
*Albert Medal of the
Royal Society of Arts(1929);
*President of the
British Association for the Advancement of Science(1932);
James Alfred Ewing Medalof the Institution of Civil Engineershas been awarded for "specially meritorious contributions to the science of engineering in the field of research" since 1938.
*cite book | author=Ewing, J.A. | title=Treatise on Earthquake Measurement | year=1883
*cite book | author=- | title=Magnetic Induction in Iron and Other Metals | year=1891 | location=London | publisher=Van Nostrand
*cite book | author=- | title=The Steam Engine and other Heat Engines | year=1894
*cite book | author=- | title=The Strength of Materials | year=1899
*cite book | author=- | title=The Mechanical Production of Gold | year=1908
*cite book | author=- | title=Thermodynamics for Engineers | year=1920
*cite book | author=- | title=The Mechanical Production of Cold | year=1921 | location=Cambridge | publisher=Cambridge University Press
*cite book | author=- | title=An Engineer's Outlook | year=1933 | publisher=Methuen | location=London
*Bates, L. F. (1946) "Sir Alfred Ewing: A Pioneer in Physics and Engineering" ISBN 1-114-51704-6
*Pedlar, Neil, 'James Alfred Ewing and his circle of pioneering physicists in Meiji Japan', Hoare, J.E. ed., "Britain & Japan: Biographical Portraits" Volume III Chapter 8. Japan Library (1999). ISBN 1-873410-89-1
Wikimedia Foundation. 2010.