Salt: The Only Rock We Eat, Oct 04 | Historical Quest for NaCl


The quiet, stable salt sitting in a shaker in your kitchen precipitates from a reaction of “an unstable metal that can suddenly burst into flame”—sodium—with “a deadly poisonous gas”—chlorine. Yet without salt, the heart, muscles, and nerves of the human body would not function. The constant need to replenish salt lost through sweat and excretion has impacted world events more than typically appreciated. Mark Kurlansky’s entertaining Salt: A World History (2002) traces the influence of this now inexpensive commodity from the Ice Age to today’s salt domes, housing strategic petroleum reserves.

When the Ice Age ended, fields of wild grains appeared. Hunter-gatherers became farmers, and it was necessary to supplement the new vegetable/grain diet with external salt. The Chinese extracted brine from underground by using bamboo piping that was not only salt-resistant, but unclogged by algae and microbes, killed by the salt. The use of bamboo piping was soon transferred by the Chinese into the first indoor plumbing. Inexplicable illnesses among the workers and occasional explosions at the mines led to the discovery of natural gas. Chinese familiarity with salt spearheaded the use of saltpeter or gunpowder. Moreover, the Chinese government monopolized the salt and used the revenues to fund expansionary adventures. If that sounds too familiar, it’s because the root of “salary” is the Latin sal for salt, because Roman soldiers were sometimes paid in salt.

Latin students may also remember Caesar’s Celtic enemy, Vercingetorix, who led a naked army, but in leisure wore Europe’s brightest garments, richly colored with salt dyes. Caesar was trying to conquer the Celts because they controlled the central European salt mines near today’s Salzburg, Austria. He called them Gauls, from the Greek word hal, meaning salt. While the Egyptians, like the Chinese, loved salted sauces over vegetables, the Romans preferred salted raw greens or salads, with olive oil preserved with salt. Later Italians, the Venetians, got rich by taxing the salt and spice trade, rather than monopolizing it like the Chinese. Why Venice? Because it was the nearest port to Salsomaggiore’s salt mines and the towns of Parma and Reggio. Parmigiano-Reggiano cheese was aged for two years till the salt reached the center of the wheel held in a mold. Forma means wooden cheese mold, hence formaggio for cheese, hence quattroformaggio (four cheese) pizza. Far outdoing Italy with four cheeses is its neighbor France’s dependency on salt, unwittingly acknowledged by DeGaulle (or DeSalt) when he quipped, “Nobody can easily bring together a nation that has 265 kinds of cheese.” Even the first tax repealed at the beginning of the French Revolution was the gabelle or salt tax that fell heaviest on the poor.

Scarcity of salt caused much suffering in the American Revolution, and in the War of 1812, the British tried to capture Cape Cod for the saltworks. The Erie Canal was built partially to transport salt more quickly from Syracuse and Onondaga, New York. During the Civil War, the blockaded Confederacy starved from lack of salt to preserve food. The situation worsened when West Virginia broke off from Virginia, and the Great Buffalo Lick at the Kanawha River went to the North. At Appomattox, Lee asked Grant for food and salt for the South.

Ironically, America’s greatest salt source was later discovered in the South, at the swampy island of Petit Anise in Louisiana. This salt combined with the hot peppers grown there by Edmund McIlhenney continues to be a success, as Tabasco sauce. The economy of the new Mormon community in Utah was jump-started by its proximity to salt. In 1911, the Morton Salt Company added magnesium chloride to keep table-salt crystals from sticking together, and, in 1924, Morton added iodine to its salt due to a recommendation from physicians. Today most Morton salt comes from Great Iguana Island in the Bahamas, but only 8 percent is used for table salt, while 51 percent is for road deicing. If you think you know why salt is less important for food preservation now, then you have hit the Birdseye. Yes, the invention of frozen food in 1925 coupled with the can opener made cured food a distant third.

Yet salt continued to impact international relations. Mahatma Gandhi liberated India by first breaking the British salt monopoly. In 1945, American troops found $3 billion in looted paintings, currency, and bullion that the Germans had stashed in the Merkers salt mine. Even so, in 2002, a third of the tourists soaking in the Dead Sea’s 26-percent salty waters are German. America stores oil and nuclear waste in salt domes, and the world eats chips and drinks sodas.