Salt: A World History

by Mark Kurlansky

TO KEEP MEAT FROM SPOILING IN SUMMER Eat it early in the Spring.—Confederate States Almanac, Macon, Georgia, 1865

San Francisco Bay salt was considered of low quality, and it did not compete easily with Liverpool salt, which came as ballast on the British ships that bought California wheat.

Today, the amount of nitrates is limited by law to what seems to have been deemed an acceptable risk for the oddly unquestioned goal of making ham reddish.

Mother liquor is the dark blood-red water that remains after common salt precipitates out of brine. An eighteenth-century London chemist named John Brown discovered that Epsom salt could be boiled out of the mother liquor without sulphuric acid. Brown also found another salt in the liquid. The study of this third salt, now known to be magnesium chloride, unleashed a chain of discoveries, including Davy’s 1808 announcement that he had found a new element, magnesium. In 1828, Antoine Bussy isolated workable quantities of the metal, and an industry was born. Magnesium is used to prevent corrosion of steel and in explosives, lightbulbs, and lightweight metal alloys.

Sodium hydrogen carbonate, bicarbonate of soda, is used in food as well as for glassmaking and textiles. Sodium carbonate is used in making paper, plastics, detergents, and the artificial fabric rayon.

Amelia Simmon’s cookbook, originally published in Hartford and then Albany in 1796, is considered the first American cookbook not only because it was published after the Revolution, but because it was written by an American, for Americans.

In 1807, when the potash industry was already many centuries old, Davy connected a piece of potash to the poles of a battery and caused the release of a metal at the negative pole. According to his cousin Edmund, Davy began dancing around the room in ecstasy, realizing that he had isolated another element. He named his newly discovered metal potassium after potash.

1786, ten years after Scheele’s observations on chlorine, that a practical application was pursued by the great French chemist Claude-Louis Berthollet, who showed that chlorine, when absorbed in potash, created a liquid bleach.

Chlorine has become an important industry. Not only used for bleach, water treatment, and sewage treatment, it is also an ingredient in plastics and artificial rubber. And, as with so many scientific discoveries, a military application was found. Chlorine was the basis for gas warfare.

later in the war, artillery shells filled with carbonyl chloride proved to be more effective. Known as mustard gas, the compound is credited with 800,000 casualties.

a salt was any substance caused by the reaction of an acid and a base.

Rouelle understood that an acid and a base have a natural affinity for each other because nature seeks completion

Acids search for an electron that they lack, and bases try to shed an extra one.

In common salt the base, or electron donor, is sodium, and the acid, or electron...

Saltworks, once contaminated by coal smoke and pan scale, expanded their line of products and became far more toxic. By the 1880s, the age of canals had come to an end with the development of railroads, and salt was no longer profitable in upstate New York. But salt was used to manufacture soda ash, caustic soda, bicarbonate of soda, and other chemicals. The salt center of Syracuse was turned into a chemical manufacturing center, temporarily saving the industry but nearly destroying Lake Onondaga with pollution. Chlorine is a component of some of the deadliest industrial pollutants, including polychlorinated biphenyls, which are more infamously known by their abbreviation, PCBs.

In 1830, a canning plant was built in La Turballe, the sardine fishing town across the opening of the Guérande swamp from Le Croisic. The plant flourished, and gradually most of the area’s salt fish business collapsed, unable to compete with canned products.

Fast freezing worked, Birdseye discovered, because of a principle every salt maker knew: Rapid crystallization creates small crystals, and slow crystallization produces large ones. Because the ice crystals in rapidly frozen food were small, they did not interfere with the tissue structure and so better preserved the food in its original state.

In 1925, Birdseye moved to Gloucester, Massachusetts, the leading New England cod-fishing port, and established a frozen seafood company.

By 1928, 1 million pounds of food frozen in the Birdseye method was being sold in the United States. Most of it was being sold by Birdseye, who managed to find a buyer for his company just before the 1929 market crash. The company became General Foods,

Fast freezing had at last made the unsalted fish people wanted, available to everyone, even far inland. Soon fishing vessels, instead of salting their catch at sea, were freezing it on board. Most salted foods became delicacies instead of necessities.

In 1840, a twenty-eight-pond saltworks near Cape Ann, Massachusetts, supplemented the power from windmills on calm days by pumping brine by means of a fifteen-foot-in-diameter, five-foot-wide wheel with buckets on its outer rim. The wheel was powered by a large bull that walked inside the wheel.

The first engine, the steam engine, which led the way to the Industrial Revolution, was invented in 1712 by an Englishman, Thomas Newcomen, and used exclusively for pumping water.

In the eighteenth and nineteenth centuries, the raging geologic debate pitted neptunism against plutonism. The neptunists, led by German mineralogist Abraham Gottlob Werner, believed that the source of all bedrock was a common ancient sea. According to plutonism, most rock had hardened from a huge molten rock mass. Neptunism held that salt came from the sea, and plutonism insisted it was volcanic in origin.

There is still not complete agreement on the formation of many of the earth’s great salt deposits. But they are generally agreed to have had their origin in oceans rather than volcanos, though there is still no set explanation for the saltiness of the sea.

in 1859, outside Titusville, Pennsylvania, where Edwin Drake, after studying the drilling techniques of salt producers, drilled 69.5 feet and, to everyone’s surprise but his, hit oil.

By 1866, seven years after Titusville, when salt was discovered in Ontario, it was a different age. Canada had not produced much salt, but instead of excitement about a rich new salt field, there were high hopes that oil had been found.

because of Spindletop, geologists took a new look at salt domes. Because salt is impenetrable, organic material gets trapped next to the salt and slowly decomposes into oil and gas. For this reason, oil, gas, or both are frequently found on the edge of salt.

In 1908, oil was found in Persia, now Iran, in the places where Herodotus had written about salt.

The quest for salt had turned unexpected corners and created dozens of industries.

The problem was that if large quantities of brine were removed, they were replaced with large quantities of freshwater that hungrily absorbed considerable amounts of salt. Once that started happening, the freshwater began eroding the natural salt pillars that supported the space between the salt rock and the surface. When a pillar collapsed, the earth above it sank.

The salt producers argued, with typical nineteenth-century capitalist confidence, that the locals were already being compensated by the economic benefits of having the salt industry. They denied that the subsidence was caused by pumping, insisting that the sinkholes were a natural phenomenon that would continue even without pumping. These arguments prevailed, and, in 1880, the bill was defeated.

In 1891, when the Cheshire Salt Districts Compensation Bill again came before Parliament, the Salt Union used the arguments that the independent salt producers had used a decade earlier:

the Salt Union provided a target, a single entity that was clearly responsible—a

It passed, though, and within ten years the Salt Union itself was applying for damages, saying its properties had suffered subsidence from the pumping of others.

Merchants came to Orissa to buy salt or barter with products such as cotton, opium, marijuana, and grains, carried by oxcart from central India. Even the British in Bengal traded in Orissa salt. They needed large quantities of salt for the manufacture of munitions for their eighteenth-century wars with the French, and a significant part of the salt for their gunpowder came from Orissa.

In 1803, in the name of fighting contraband, the British army occupied Orissa and annexed it to Bengal. On November 1, 1804, by proclamation, Orissa salt became a British monopoly. The private sale of salt was completely prohibited. Those who had salt in their possession had to sell it to the government immediately at a fixed price.

Within ten years, it became illegal for salt to be manufactured by anyone other than the British government.

In 1834, a zealous commissioner of customs, G. H. Smith, was appointed, and in his twenty years in office he expanded the system into a “Customs Line” around Bengal. Salt had to pay a duty to cross this line.

In the 1840s, in its enthusiasm for enforcing this line, the East India Company constructed a fourteen-foot-high, twelve-foot-thick thorn hedge on the western side of Bengal to prevent the entry of contraband salt. After the British government took over following the 1857 “mutiny,” as the uprising was labeled, the Customs Line grew until it snaked arbitrarily 2,500 miles across India from the Himalayas to Orissa.

By 1870, the Customs Line, largely dedicated to the enforcement of the salt tax, employed 12,000 people.

contrary to popular belief today, it was not an entirely original idea to focus rebellion on salt, when that idea was seized upon by an entirely original man named Mohandas Karamchand Gandhi.

In South Africa he became the leader of a movement to secure civil rights for Indians. Imprisoned for his efforts, he read Henry David Thoreau’s Civil Disobedience in the appropriate setting—a jail cell. Along with Buddhist and Jainist writings, Thoreau was to have an enormous influence on him. He was struck by Thoreau’s assertion: “The only obligation which I have a right to assume is to do at any time what I think right.”

Gandhi

Seeking a name for his brand of resistance, he took a suggestion from his cousin, Maganlal Gandhi: sadagraha—firmness in a good cause. Mohandas changed sada to satya, which means “truth.” Gandhi would resist with satyagraha—the force of truth, a force that, he said, would lift both sides.

Until a peace treaty was signed with Israel in 1996, the Jordanian Dead Sea region was a military zone, off limits to civilians. Now, at peace, Jordan has few resources but is full of plans. Mohammed Noufal observed with a smile, “All we need is Israel’s technology, Egypt’s workers, Turkey’s water, and Saudi Arabia’s oil, and I am sure we can build a paradise here.”

In Chinese folk literature, the salt smuggler is always a hero fighting the evil and corrupt salt administration. The villain of the story is often not the government but the Yuen Shang.

The Yangtze, the 3,700-mile waterway from the Tibetan mountains to the port of Shanghai, the third-longest river in the world, divides China into its north and south, and yet, until the 1949 Communist victory, China had so little transportation infrastructure that there was not a single bridge crossing it.

Salt-cured lox, once the leading cured salmon, has in recent years been almost completely abandoned for the less salty Nova, a lighter cure, soaked in brine and then smoked.

The name comes from Nova Scotia, though most Nova originally came from the nearby Gaspé Peninsula of Quebec. Now there is western Nova, made from Pacific salmon, because Atlantic salmon has all but disappeared except for farmed varieties. Moe Greengrass, owner of a popular Jewish smoked fish store on Manhattan’s Upper West Side started by his father in 1929, said, “Nobody buys lox anymore—we sell 100 pounds of Nova and 5 pounds of lox per week.”

these days Sicilians don’t eat their bluefin tuna in any form; they sell it fresh for dazzlingly high prices. Ninety percent of the local catch is landed one hour after being killed and instantly sold and flown to Japan.

Morton Salt Company was now both a distributor and a producer. One of its early innovations, in 1911, was the addition of magnesium carbonate to table salt, which kept the salt crystals from sticking together; as stated on the box, the salt “never cakes or hardens.” Eventually, the chemical was replaced with another nonsticking agent, calcium silicate. This nonsticking quality was to become the basis of Morton’s famous marketing campaign. Another innovation: In 1924, on the recommendation of the Michigan Medical Association, Morton produced the first iodized salt.