Nitre [N] [S]
( Proverbs 25:20 ; RSV 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 ( Jeremiah 2:22 ; RSV "lye").
These dictionary topics are from
M.G. Easton M.A., D.D., Illustrated Bible Dictionary, Third Edition,
published by Thomas Nelson, 1897. Public Domain, copy freely.
[N] indicates this entry was also found in Nave's Topical Bible
[S] indicates this entry was also found in Smith's Bible Dictionary
Bibliography InformationEaston, Matthew George. "Entry for Nitre". "Easton's Bible Dictionary". .