Nitre: (Proverbs 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
(Jeremiah 2:22) R.V. "lye".