Salt: A World History

“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.”

A paradox in the book is that salt is everywhere, accessible to most, and yet has historically been treated as if it were scarce. Such scarcities were manufactured by merchants’ purchasing of competitors, violent enforcement by agents such as the gabelous, and government regulation. The section on British control of Indian salt is a particularly egregious example thereof. 

“Baby formula contains three salts: magnesium chloride, potassium chloride, and sodium chloride.”

In light of later comments about salt’s potential influence on health, it is notable that the feeding of infants will generally include at least three forms of salt. It is also true that most people, including new parents, are unlikely to be able to enumerate the potential benefits—or harms—of different types of salts. In this way, although salt is now better understood than ever before, the lay knowledge of sodium remains narrow. 

“In every age, people are certain that only things they have deemed valuable have true value. The search for love and the search for wealth are always the two best stories. But while a love story is timeless, the story of a quest for wealth, given enough time, will always seem like the vain pursuit of a mirage.”

A definition of wealth requires an accurate definition of value, but as Kurlansky shows throughout the book, value is a slippery concept. A person who pursues wealth—including the many figures in the book who grow wealthy through salt—rarely stop trying to acquire more. 

“Toward the end of the first century A.D., a Confucian government minister had them once more abolished, declaring, ‘Government sale of salt means competing with subjects for profit. These are not measures fit for wise rulers.’”

In both the case of the French and the case of the Chinese, struggles over salt taxes pitted government officials against the public. A government is supposed to serve its populace, rather than seeking to use it for gain. But the Chinese government, as well as the French monarchy and the British monarchy, used its respective citizens as means to enrich themselves. They did not govern the people in order to create a just and good society, but rather to serve their own interests. 

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

The study of salt would yield great innovations in chemistry and cooking, and provide a better understanding of human biology. Once it was known that a salt could interact with a protein in this way, questions arose about what other reactions it might produce in other substances, or what other substances might produce in salt, when added to salt. 

“Trade in salted food would shape economies for the next four millennia.”

Few things have the power to influence the lives of people like the economies into which they are born, and Kurlansky shows that few things had more influence over early economies than salt. The effects of those economies continue in modern times. Choices made by early salt magnates still manifest in the lives of people in the 21st century. 

“The Roman army required salt for its soldiers and for its horses and livestock. 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 world solde, meaning pay, which is the origin of the word, soldier.”

The idea of salt as a military necessity appears several times in the book. It is difficult for a modern reader to imagine being paid in salt, rather than money, which gives insight into how crucial salt was. 

“Although there may be someone who does not seek gold, there never yet lived the man who does not desire salt.”

Salt is presented throughout the book as an object of desire, even by those who do not consciously seek it. Desire is pursued due to appetite, and the human appetite for salt has historically been profound. This is also an echo of the former remark that the hunt for wealth has the character of a man searching for a mirage: it is always just a little bit further away.  

“Venice manipulated markets by controlling production. In the late 

thirteenth century, wishing to raise the world market price, Venice had all saltworks in Crete destroyed and banned the local production of salt.”

A willingness to destroy property for profit is indicative of the greed that salt profits could induce in people, and in entire governments. Venice mobilized military fleets, passed legislation, and created demolition teams just to ensure that it could continue to make as much money as possible off of salt. It was also willing to take away the livelihoods of people who, up to that point, had made their living off of making or selling salt. 

“According to Seneca, Apicius committed suicide because, having spent one tenth of a considerable fortune on his kitchen, he realized he could no longer continue in the style he had chosen.”

This quote is a melodramatic example of how seriously some people in the ancient world took their food and their salt. Salt was obviously not simply an enhancement of some people’s lives, but a part of their lifestyle—a status symbol. Apicius apparently considered a life without constant access to salt a life not worth living. 

“It takes two years for the salt to reach the center of a wheel of Parmigiano-Reggiano cheese.”

Salt allowed French cheesemasters to experiment with new styles and techniques for making cheese. The two-year aging period shows the patience that cheesemakers had, and the importance that was placed on innovative cuisine. It also shows a willingness to experiment on behalf of improved cuisine, even if it takes years. 

“The salt intake of Europeans, much of it in the form of salted fish, rose from forty grams a day per person in the sixteenth century to seventy grams in the eighteenth century.”

As the fishing industry grew, so did the salt intake of Europeans. The amount of salt consumed would continue to grow, as well, with advances in butter preservation and cheesemaking. As more products entered the markets, there were more opportunities for those who profited from preservation. But the increase in salt consumption was a negative sign for those who worry about the deleterious effects of salt on a person’s health. 

“The first experiments in refrigeration were not with fish or meat but with everyone’s favorite luxury—butter.”

Butter was poorly preserved by salt, which led to innovations in refrigeration. In turn, refrigeration would help dismantle great swaths of the salt industry, since salt was no longer necessary for all forms of preservation. Salt’s decline was often preceded by a new wave of enthusiasm for another product, such as butter or cheese. Refrigeration both accelerated the rise of other products and changed the world’s relationship to the most common uses for salt. 

“When these early settlers hunted, they would leave red herring along their trail because the strong smell would confuse wolves, which is the origin of the expression red herring, meaning ‘a false trail.’”

This is one of many examples of how salt has shaped linguistic development and idiomatic expression. Every time someone says the word “salary,” they are using a word that derives from the Latin for salt. Every time someone uses a “pinch of salt” for luck, or they “take something with a grain of salt,” they are reenacting old superstitions and maxims. 

“It is an old remark, that all arts and sciences have a mutual dependence upon each other. Thus men, very different in genius and pursuits, become mutually subservient to each other; and a very useful kind of commerce is established by which the old arts are improved, and new ones daily invented.”

This quote is from William Brownrigg’s 1748 book The Art of Making Common Salt. The quote works as a metaphor showing how the pursuit of salt has bound people together who might otherwise never have encountered each other. It also reinforces that the discoveries concerning salt did not occur in a vacuum: they would go on to influence and encourage discoveries in other fields.

“The name potash is derived from the process for making potassium 

carbonate, cooking down water and wood ash in earthen pots.”

Many types of salt are named for the methods by which they are made. Kurlansky’s discussion of potash also makes clear that many people have no idea what might be in their salt (such as wood ash). Until the 17th century, potash was indistinguishable, for most people, as a different type of salt. Different varieties of salt were often named after the locations in which they were discovered or produced. 

“A salt is a small but perfect thing.”

Before the electrolysis experiments of Davy, little was known about salt, save for its appearance and taste. But Davy’s chemical experiments revealed that salt has properties that are as close to perfection as molecular compounds can be. Salt had the potential to unlock chemical mysteries that could not be solved without it. Without the simplicity of salt and an electrical current, the discovery of magnesium, potassium, chlorine, and other elements would have been delayed. 

“As a result of Spindletop, the United States surpassed Russia, the largest oil producer at the time.”

The oil boom in America was a result of drilling at the Texas salt dome of Spindletop, which was also a boon during the hostilities of the Cold War. Without the exploration for salt, the discovery of American oil would have been delayed. Without the rise of geological knowledge, it may never have occurred to anyone to treat a salt dome as having potentially different properties—such as their likelihood to be near oil—as other salt formations. 

“Chemistry changed forever the way we see salt. But it was inventions in other fields that radically changed the role of salt in the world.” 

After the Industrial Revolution, the importance of salt as a preservative diminished. Canning and tinning were soon being used to preserve food. This meant that ventures such as arctic explorations and military campaigns no longer depended on salt, and also that less salt was being consumed by people who needed to be in peak physical condition. 

“It would be folly to assume that an Indian Rockefeller would be better than an American Rockefeller.”

Even as he fights for Indian independence, Gandhi is vigilant against the appearance of Indian monopolies or despots. He understands human nature well enough to know that no one is immune to the allure of the power, and in this case, the power that comes from the control of salt. Even as he lives by humble means and leads by example, Gandhi acknowledges that even he could be corrupted if he allowed himself to give in to temptation. 

“Transportation was always the key to the salt business, and Morton was a company founded on a transportation idea.”

The only people who reaped exorbitant profits from salt were those who with the ability to move it. Infrastructure mattered as much as volume in salt production. This was obvious in the construction of Rome’s Via Salaria, one of the empire’s most important roads. It was designed with the transport of commodities in mind, and especially salt. 

“The United States is both the largest salt producer and the largest salt  

consumer. It produces over 40 million metric tons of salt a year, which earns more than $1 billion in sales revenue.” 

If salt is damaging to health, America is in a position to be unhealthier than other countries, given the sheer volume of its production. But the majority of salt in America is used for things other than a seasoning for food. Roads are deiced by industrial salt, accounting for 51 percent of America’s salt production.

“Modern people have seen too many chemicals and are ready to go back to eating dirt.”

In his discussion about the healthy and detrimental effects of salt, Kurlansky points out an irony: the refinements to salt have required greater chemical experimentation. People have finally grown reluctant to add more chemicals to their diet and wish to return to something simpler. His comment is not meant as a joke, either, as salt is the only rock that people eat.