Salt: A World History

by Mark Kurlansky

In his 1776 treatise on capitalism, The Wealth of Nations, Adam Smith pointed out that almost anything of value could be used for money. He cited as examples tobacco, sugar, dried cod, and cattle and stated that “salt is said to be a common instrument of commerce and exchanges in Abyssinia.” But he offered the opinion that the best currency was made of metal because it was physically durable, even if its value was as ephemeral as other commodities. Today, thousands of years of coveting, fighting over, hoarding, taxing, and searching for salt appear picturesque and slightly foolish. The seventeenth-century British leaders who spoke with urgency about the dangerous national dependence on French sea salt seem somehow more comic than contemporary leaders concerned with a dependence on foreign oil. In every age, people are certain that only the things they have deemed valuable have true value.

Fat resists salt and slows the rate at which salt impregnates fish. This is why oily fish, after salting, must be pressed tightly in barrels to be preserved, whereas cod can be simply laid in salt. Also, fatty fish cannot be exposed to air in curing because the fat will become rancid. Cod, along with its relatives including haddock and whiting, can be air-dried before salting, which makes for a particularly effective cure that would be difficult with oily fish such as anchovy or herring.

Cato suggested that women would live long, healthy lives if they washed their genitals in the urine of a cabbage eater.