Salt of the Earth: We Can’t Live without It

• "Not worth his salt."
• "Rub salt in a wound."
• "True to his salt."
• "Salt an invoice"
• "With a grain of salt."
• "Salty wit, salty personality, salty dog."
• "Salad, salsa, salami."
• "True to his salt."

There's salt at the root of all of these words. In ancient Rome, soldiers were paid in salt; a salarium, or "salary".

Salt runs through the English language in a thick vein; and no wonder, since it runs the same way through history, religion, folktales, superstitions, geology, physiology, and nearly every aspect of daily living, from cosmetics and clothing to gasoline and our meals.

Salt—sodium chloride (NaCl)—is essential to the health of the planet and every living creature on it

• History has been shaped by the need for salt.
• Civilizations rose in Africa, China, India, and the Middle East around rich salt deposits.
• The desire for salt brought Phoenician trade ships into the Mediterranean and camel caravans into the deserts of Africa and across the Euphrates Valley.
• Salt bought slaves and at times was traded at a value twice that of gold.
• Marco Polo discovered that Tibetans used salt cakes stamped with the imperial seal of the great Kublai Khan as money.
• Men have fought over salt with clubs, arrows, and cannon.
• Because everyone, rich and poor, craves salt, rulers going back at least as far as the Chinese emperor Yu in 2200 B.C. have tried mightily to control and tax it.
• Salt taxes helped finance empires throughout Europe and Asia, but it also inspired a lively black market, smuggling rings, riots, even revolutions.
• In 1785, the earl of Dundonald wrote that every year in England, "ten thousand people are seized for salt smuggling and three hundred men are sent to the gallows for contraband trade in salt and tobacco."
• A few years later, hogs and cattle started to die in Britain for lack of salt; because farmers couldn't afford the exorbitant royal tax.
• As angry mobs stormed across the countryside, Parliament was forced to abolish the tax.
• France's long-despised tax on salt, under the rule of Louis XVI, is believed by some historians to have brought about the French Revolution.
• The new revolutionary-French Assembly quickly ended the tax in 1790, ensuring affordable salt for everyone, but it was a short-lived symbol of democracy and freedom from tyranny because the salt tax was soon re-established, not to be abolished again in France until 1946.
• Mahatma Gandhi started India on the path to independence in 1930 by undertaking a 200-mile march to the sea to protest Britain's salt tax and its prohibition against gathering one's own sea salt, which Gandhi denounced as intolerable assaults on autonomy and basic human rights.

Humans have collected and made salt since prehistoric times

• People who lived near oceans gathered saline crust from shore rocks and dry tidal pools.
• With other predators, they hunted the animals drawn to salt spring and licks, and no doubt sought salt at such places themselves.

The Romans and the importance of salt

• When Julius Caesar invaded Britain in 55 B.C., he found the natives producing salt by pouring brine over hot sticks and scraping off the leftover glaze, a practice that helped confirm them in his mind as barbarians.
• Caesar always traveled with "salinators" who were skilled at providing salt for his troops.
• Those experts showed the "loutish Brits" how to boil brine, as the Romans had been doing for centuries.
• Salt is said to have inspired Rome's first step toward being an empire, and the first spoke in its renowned system of roads.
• King Ancus Martius (640-16 B.C.) founded its first colony at Ostia because of the salt marshes there, and the Via Salaria (Salt Road) was built to carry processed salt to the city.
• As the empire expanded, so did the demand for salt.
• Rome started to import it from Cyprus, France, North Africa, and even as far away as Palestine and Asia Minor.
• It was taxed, of course, and officials were appointed to control the trade.
• Salt became one of the world's first commodities not only because people hungered for it, but because of its crucial role in religion.
• Some people are superstitious about spilling salt because it is supposed to bring bad luck.
• This superstition is immortalized in Leonardo da Vinci's painting "The Last Supper", where Judas is shown to have knocked over the saltcellar (a small dish for holding salt at the table). It has nothing to do with a basement or cellar.

Salt has had a long history of processing

• The basic methods of salt production haven't changed for centuries; that is, boil, evaporate, mine.
• Modern salt makers still boil brine or let the sun evaporate it.
• At Cargill's solar plant on the Great Salt Lake in Grantsville, Utah, salt is "farmed".
• The lake has a salinity of more than four times that of the ocean.
• Each spring, water from the lake is moved into a series of big concentrator ponds, where sun and wind slowly pull off the moisture.
• Workers channel this saturated brine into crystallizer or "garden" ponds, where more evaporation causes the brine to bond into crystals, which fall to the bottom.
• Calcium, magnesium, and other natural impurities that would embitter the salt are returned to the lake.
• Usually during September, a new crop of salt, 99.2 percent pure, lies four to six inches thick in the ponds.
• At harvest-time, the ponds are drained, resulting in a smooth, rock-hard field of white.
• A specialized harvester slices through the salt and dumps it into trucks which empty their loads into hoppers of brine to float off impurities such as tumbleweeds.
• Screens remove the fine dust particles and other unwanted grit.
• After draining for weeks, the salt gets conveyed into the plant, where it is dried, screened, crushed, and packaged in numerous ways.
• Cargill's Utah salt farm produces about half a million tons of salt a year.
• Eighty percent of it goes for water conditioning, to remove the calcium and magnesium that make most water hard.
• Just add salt, and dishes sparkle, hair shines, soap suds up better, clothes come out cleaner and more supple, nozzles don't clog, and minerals don't build up in the pipes.
• Besides a few specialty customers; such as, the Montana pickle maker who requires a super sack of salt weighing 2,250 pounds, farmers claim the rest of the salt crop.
• Cows, sheep and chickens, like humans, need salt.
• If they don’t get enough of it, they lose weight and appetite, and in their craving will eat dirt, rocks, and wood, or lick the urine and sweat of other animals.
• Salt-deprived chickens become runty and nervous, and produce smaller, fewer eggs.
• By contrast, calves on salt supplements gain weight twice as fast as their unsalted companions.
• Salt is so popular in the barnyard that farmers use it to "deliver" other important nutrients and minerals: such as, iodine, zinc, and cobalt.
• It has been a long journey from ancient Britons scraping saline crusts to our modern appetite for salt and yet the meanings we attach to it have linked the ages in a common interest.
• Salt literally gives us life, and reminds us of the origins of all life in the primordial sea. It has motivated the pious, the warlike, the superstitious, and revolutionaries.

The unit of salt words is located here.