From the Enc. Brit. I got the following quotation:
Ewing, Sir (James) Alfred
(b. March 27, 1855, Dundee, Angus, Scot.--d. Jan. 7, 1935, Cambridge,
Cambridgeshire, Eng.), British physicist who discovered and named
hysteresis, the resistance of magnetic materials to change in magnetic
force.
Ewing was professor of mechanical engineering at the University of Tokyo
(1878-83) and professor of mechanism and applied mechanics at King's
College,
Cambridge (1890-1903). In his work on the magnetic properties of iron,
steel, and other metals, he succeeded in modifying Wilhelm E. Weber's theory
of induced
magnetism and constructed a hypothetical model to fit his own theory. In
1890 he observed that in electromagnets using alternating current, the
magnetization of the
metal lagged behind the changing of the current flow. He conjectured that
all molecules are like tiny magnets and explained hysteresis as a resistance
of the
molecules to rearranging themselves in alignment with the new direction of
magnetic force. Ewing wrote a number of papers on thermoelectric properties
of metals,
on the effects of stress and magnetization on iron, on the crystalline
structure of metals, and on seismology. He invented an extensometer (a
device for measuring
small increases in length of metals), a hysteresis tester, and other
apparatus for magnetic testing.
He was director of naval education to the British Admiralty from 1903 until
1916, when he became principal and vice chancellor of the University of
Edinburgh. He
was knighted in 1911, and from 1914 to 1917 he was in charge of the
department of the Admiralty dealing with enemy ciphers.
My question is: why called Sir (James) Alfred Ewing this effect
'hysteresis', a word derived from the Greek word for 'uterus'. Or is there
another Greek word meaning something else?
Rik
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