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James Prescott Joule and the Unit of Energy


A CENTURY has passed since Joule read his paper on the relation between heat and work at the meeting of the British Association at Cork on August 26, 1843. It is unfortunate that a difference of opinion has arisen about the correct pronunciation of his name and also of the word joule used to denote a unit of energy (ten million ergs or one Newton-metre). The “Oxford English Dictionary” gives dzaul as the pronunciation of the unit, where au represents the sound in the word loud. In “Webster's New International Dictionary” (1911) is found the statement: “The proper name is pronounced joul (ou as in out) and this is the correct pronunciation for the unit ; but the incorrect j\(\overline{oo}\)l [\(\overline{oo}\) as in f\(\overline{oo}\)d] is very common especially in the United States”. In “Chambers's Technical Dictionary” (first published 1940) we find the contradictory statements joule, jool (Phys.). A unit of energy equal to 107 ergs. (Named after F. [sic] P. Joule, 1918–89 ; name pronounced jowl.)

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ALLEN, H. James Prescott Joule and the Unit of Energy. Nature 152, 354 (1943).

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