Salt: A World History

At times soldiers were even paid in salt, which was the origin of the word salary and the expression “worth his salt” or “earning his salt.” In fact, the Latin word sal became the French word solde, meaning pay, which is the origin of the word, soldier.

Salt is a chemical term for a substance produced by the reaction of an acid with a base. When sodium, an unstable metal that can suddenly burst into flame, reacts with a deadly poisonous gas known as chlorine, it becomes the staple food sodium chloride, NaCl, from the only family of rocks eaten by humans.

Salt is so common, so easy to obtain, and so inexpensive that we have forgotten that from the beginning of civilization until about 100 years ago, salt was one of the most sought-after commodities in human history.

The Romans, Jones pointed out, called a man in love salax, in a salted state, which is the origin of the word salacious.

Both under the republic and, later, the empire, Roman government periodically subsidized the price of salt to ensure that it was easily affordable for plebeians. It was a gift, like a tax cut, that government could bestow when in need of popular support.

On Friday nights Jews dip the Sabbath bread in salt. In Judaism, bread is a symbol of food, which is a gift from God, and dipping the bread in salt preserves it—keeps the agreement between God and his people.

Proteins unwind when exposed to heat, and they do the same when exposed to salt. So salting has an effect resembling cooking.

Where people ate a diet consisting largely of grains and vegetables, supplemented by the meat of slaughtered domestic farm animals, procuring salt became a necessity of life, giving it great symbolic importance and economic value. Salt became one of the first international commodities of trade; its production was one of the first industries and, inevitably, the first state monopoly.

THE ROMANS SALTED their greens, believing this to counteract the natural bitterness, which is the origin of the word salad, salted.

It was the seventeenth-century English who gave corned beef its name—corns being any kind of small bits, in this case salt crystals.