Scottish National Dictionary (1700–)
Hide Quotations Hide Etymology
About this entry:
First published 1976 (SND Vol. X, list of scientific terms with Scottish connections).
This entry has not been updated since then but may contain minor corrections and revisions.
JOULE-THOMSON EFFECT. Chem. The fall in temperature which occurs in a gas which expands without doing external work, observed by J. P. Joule and Sir William Thomson c.1862. See Kelvin below.