Coomb (unit)

{{Short description|Measure of volume}}

{{Cleanup bare URLs|date=September 2022}}

A coomb is a measure of volume. Its exact original details are not known. In 13th century England it was defined as 4 bushels (~140 L). It was in use in Norfolk as a dry measure: "Ben sold my Wheat to the Marlingford Miller this Morning for 19 shillings per Coomb" - Parson Woodforde's Diary, 20 May 1786. The 4-bushel bag was the standard international shipping unit for grain,http://www.collectionsaustralia.net/nqr/wendy.php{{cite web| url = http://www.bordermail.com.au/story/570601/grain-waves/| title = Grain waves {{!}} The Border Mail {{!}} Wodonga, VIC| date = 3 November 2012}}{{cite web |url=http://www.friendsofpurton.org.uk/Vessels/Ada.html |title=Purton Vessels Ada |website=www.friendsofpurton.org.uk |url-status=dead |archive-url=https://web.archive.org/web/20120515075731/http://www.friendsofpurton.org.uk/Vessels/Ada.html |archive-date=2012-05-15}} and the coomb was in common use in farming in Norfolk and Suffolk until well after the end of World War II, in fact for as long as grain was handled in sacks, a practice which ended with the introduction of combine harvesters which had bulk grain tanks.

Yields were referred to in coombs per acre. A coomb was {{convert|16|st|kg}} for barley and {{convert|18|st|kg}} for wheat.

The US grain markets quote prices as cents per bushel, and a US bushel of grain is about {{convert|61|lb|kg|abbr=on}}, which would approximately correspond to the 4-bushel coomb (4 × 61 lb = {{convert|244|lb|kg|disp=x|abbr=on| ≈ }}).