Nitre
Easton's Bible Dictionary
(Prov 25:20; R.V. marg., “soda”), properly “natron,” a substance so called because, rising from the bottom of the Lake Natron in Egypt, it becomes dry and hard in the sun, and is the soda which effervesces when vinegar is poured on it. It is a carbonate of soda, not saltpetre, which the word generally denotes (Jer 2:22; R.V. “lye”).
International Standard Bible Encyclopedia
ni'-ter (nether; nitron): Nitre as used in the King James Version does not correspond to the present use of that term. Nitre or niter is now applied to sodium or potassium nitrate. The writer has in his collection a specimen of sodium carbonate, called in Arabic naTrun, which was taken from the extensive deposits in Lower Egypt where it is found as a deposit underneath a layer of common salt. Similar deposits are found in Syria and Asia Minor. This is probably the "nitre" of the Bible. the American Standard Revised Version has rendered niter "lye" in Jer 2:22, and "soda" in Prov 25:20. Soda or lye has been used as a cleansing agent from earliest times. It effervesces energetically, when treated with an acid; hence, the comparison in Prov 25:20 of the heavy-hearted man roiled by the sound of singing to the sizzling of soda on which vinegar has been poured.
See VINEGAR.
James A. Patch
Kilde: Easton's Bible Dictionary (M.G. Easton, 1897) og International Standard Bible Encyclopedia (red. James Orr, 1915/1939), public domain. Translated into Danish with AI and not yet proofread (fully or partially). Links to people and places: Theographic Bible Metadata (CC BY-SA 4.0).