Salt, Particularly in Ancient China and Rome

Salt--sodium chloride--is absolutely necessary to the functioning of the human body at the cellular level. Think about all the liquids that flow within and from human bodies: blood, mucus, tears, sweat, urine, and semen. They’re all salty. The fact that they flow from the body means that humans constantly lose salt. Therefore salt is a necessity; pepper is always a luxury. Humans who adopted agriculture--remember that probably 80% or more of their calories came from a starchy plant (grains or tubers)--had a lot less salt in their regular diets, so they needed to find additional sources of salt to survive. Farmers with domesticated animals which could not roam free to find salt licks also needed to supply salt to their livestock (often several times a human’s salt needs). Pastoralists and foragers often consumed enough salt normally in their diets, so they rarely needed to find extra.

Salt had other uses. Salt could be used to preserve foods that otherwise might have rotted: think dried fish and bacon, pickles and olives, and cheese. Salt is also a tool for “controlled rotting” in foods like kimchee, fish sauce, soy sauce, tofu, and sauerkraut. Stored food that does not spoil is vital to farmers who cannot grow their crops year-round. Mummification, medicines, the processing of leather, and smelting metals also required certain salts.

Getting and Making Salt
Natural salt deposits often lie underground, particularly in deserts, so it may be mined. Natural evaporation pans (pools at the sea shore or lakes in arid regions) are a very useful means of getting salt. As long as the area is dry and sunny, the sun itself puts in the energy necessary to evaporate the water and leave the salt behind. However, if an area is wet, cool, and/or cloudy, human inputs of energy are required to evaporate the water. In these cases, the costs of fuel have an impact on the cost of the end product of salt. As two scholars argue, “Salt production, in many ways, was the world’s first industry.” In some inland areas, salt-water springs flow from the earth, and these are often places where human settlements appear. People can also burn some sorts of vegetation, and by processing the ashes produce salt.

Since salt was essential to the lives of all farmers, governments realized it was a good commodity to tax, since a salt tax would ensure a perpetual revenue. In many cases, the production and distribution of salt was critical to state power. “[S]alt touched on almost every aspect of the lives of most pre-modern farming societies. The availability and variety of salt could determine the types of food people ate. Efforts to produce salt could encourage technological innovation and influence the nature and allocation of labor. Trade linkages that brought salt could also lead to substantial cultural exchange between societies. And finally, salt could play a critical role in determining the very nature of the relationship between the rulers and the ruled.”

In the Ancient Roman Empire
Rome itself might have been established (6th century BCE) as a salt-trading center. Humans made salt ponds on the edge of the Mediterranean and mined it in the Alps. For salt production, the Romans were not inventive, but they borrowed any useful techniques from the peoples they conquered.

Romans salted their fresh foods typically in two ways. Most meals were served with a fermented fish sauce (called garum or liquimen) as a condiment. Greens that were eaten were typically salted; this is the origin of the English word “salad.” Salt-soaked olives were eaten by all classes of Romans, but they were a staple food for plebeians and slaves. Elaborate silver saltcellars were fashioned and purchased to show off wealth at the table.

“Salarium argentum,” or the salt money paid to Roman soldiers as part of their wage, persists in the English language in the word “salary.” The cliché “worth his salt” has origins in this time. Horses in the large Roman army needed salt, too. The cost of salt sometimes was subsidized by the Roman government to gain popular support, since the price went down for commoners. At other times, the Roman government (like during the Punic wars in the 2nd century BCE) intervened in price-setting to raise extra taxes, very much like contemporaneous Chinese governments. The Punic wars were intended to destroy the Phoenician trading network. The purple dye that Phoenicians traded which gave them their name was actually extracted by salting a particular shellfish. This process took long enough (and so many mollusks) that purple dye was very rare in large quantities, and therefore became something only the elite wore in the Mediterranean. Once the Romans conquered the Phoenician city-states they discovered this secret process. Julius Caesar outlawed purple clothes for anyone outside his family (1st century BCE).

In Ancient China
The earliest written records for Chinese salt production date from around 800 BCE. Iron pans--some as large as ten feet in diameter--came into use for making salt roughly contemporaneous with Confucius (5th century BCE). Mencius (4th century BCE), one of the more famous Confucian scholars, was allegedly a salt-merchant as well (interesting considering Confucian dogma regarding trade).

The production of salt led to much technological innovation in ancient (and medieval) China. In the Sichuan (Szechuan) province in the middle of the 3rd century BCE (252), a government official by the name of Li Bing realized that standalone salty pools were getting their salt from somewhere underground. He began to organize digging--which eventually turned into drilling--to acquire that salt. Soon the mineshafts were sunk to 300 feet underground. Trouble soon befell the miners sent underground: they would get weak, fall unconscious, and die. Every once and a while the mines would explode in flame, killing the workers. This was blamed on evil spirits escaping, but eventually, by 100 CE, the Chinese learned to control these “spirits,” which were, of course, natural gas. They lit flames at the surface where the gas was escaping, and since these were perpetual fires, began to use this “free” energy to cook and boil salt brine. Shortly thereafter elaborate bamboo pipe systems were constructed to send the natural gas some distance from the mines (very much like gas stoves in the present, only without much in the way of shutoff valves). (This bamboo piping technology spread to other parts of China, and used in elaborate urban plumbing systems by the year 1000 CE). These natural gas works were efficient enough that they continued to be used into the 20th century (CE).

The seven necessities of daily Chinese peasant life were named as firewood, grain, oil, salt, soy sauce, vinegar, and tea. Like the Romans, the ancient Chinese initially used fish sauce or paste, but eventually substituted fermented and salted soy sauce in their cuisine. Pickled vegetables and eggs--made with salt--were vital to the Chinese diet.

Chinese officials often organized the production of salt, and required families in salt-producing areas to manufacture a particular quota each year, effectively taxing their labor for the government. Because cooking up salt required a lot of carefully-timed procedures, this work could consume the whole family for weeks. One of the early Chinese pictographs for salt was essentially an abstract drying pan. By the Han era (2nd century BCE), the word for salt included an abstract government official, suggesting that salt and the government are inseparable.

The Legalists--whose ideology was ascendant in the 3rd century BCE--advocated fixing a price for salt, but allowing the government to buy it at a lower price, using the profit when sold to the population as the tax. This may have been the first state-controlled monopoly of a vital commodity when it was implemented under the rule of the short-lived Qin Dynasty. The revenues went to pay soldiers’ salaries and to fund the construction of the early elements of the Great Wall. The Chinese government’s salt monopoly came and went depending on prevailing ideas of what good government was and the needs of the state to scare up additional revenue. For example, when the Xiongnu pastoralists continued to threaten the Han frontier in 120 BCE, and the government had spent most of its cash, it re-established the monopoly on selling salt (and added monopolies on iron, wine, and beer). Although this tax was very effective, the state organized a scholarly debate on the necessity of the salt monopoly in 81 BCE. When the monopolies were in force, there were drawbacks. Prices for salt went up, of course, so many smuggled salt and some Chinese subjects even turned to banditry of government salt caravans.

Sources: Mark Kurlansky, Salt: A World History (2003); Erik Gilbert and Jonathan Reynolds, Trading Tastes (2006).

--To Pepper--

Gilbert and Reynolds, 17.

Gilbert and Reynolds, 18.

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