Salt

The human body requires between five and ten grams of salt a day. Humans need a daily intake of salt. Unlike other chemicals that the body requires, sodium chloride, or salt, cannot be reproduced by the body. Sodium chloride is used as an electrolyte. An electrolyte is “a solution or substance in a solution consisting of various chemicals that can carry electric charges. Electrolytes exist in the blood as acids, bases, and salts.”[1] Salt is needed by the human body in order to help muscles and nerves to work and to regulate blood pressure. Hormones help the body regulate how much salt and water is needed. If the body has too much salt the excess sodium chloride is excreted. If the body has too little salt more water is excreted from the body in order to preserve the BrCl/H2O balance in the body. If the human body goes for a long period of time without enough salt the body will desiccate and die.

There are two main reasons why humans began trading in salt.  First with the development of agriculture, there was less salt in the diet of humans for they were eating less meat.  If humans had smaller portions of meat in their diet it meant having less salt in their system.  They needed to obtain salt somehow.  The second reason why humans would trade in salt is the domestication of animals.  Animals like humans need salt in their diets and humans needed to find a way of supplying that need. Early Humans obtained salt from the blood of animals that they ate.  As the human population grew so did their reliance on agriculture. The local environment usually did not have enough game to allow everyone in the population to eat meat on a regular basis and the crops that humans grew did not meet the salt requirements of the body.  Humans had to find another way to obtain salt.  They had to find sources of salt that occurred naturally in nature and somehow incorporate salt into their diets.  Salt can be found along dry coastlines, salt springs, and salt-bearing rocks known as halite. Salt is very easy to collect but is very time consuming. In open pan salt making salt is collected from brine, which is boiled in large flat uncovered pans. Since salt is a commodity that no human can do without, people who had an abundance of salt could trade their surplus for goods with people that did not have a way of obtaining salt. Rock salt and earth salt are the two varieties of salt that are produced in the Western Sahara.  Rock salt is a naturally occurring salt that is found underground and earth salt is also a naturally occurring salt that can be found aboveground.  Both of these salts were highly valued for they are easy to transport, are not easily affected by moisture, meet the saline requirements of animals and humans, and could also be used as a form of currency.

Three great civilizations profited from controlling salt in various aspects; China, Egypt, and the Roman Empire.  The Chinese Emperors had control over the price of salt and used the money that was raised to finance armies and public works, including the Great Wall of China.  The Egyptians who had numerous ways of obtaining salt also benefited from their surplus.  They could gather salt from dried salt lakes and salt deposits and from evaporating seawater from the Nile Delta.  The Egyptians also obtained salt through trade with Libya and Ethiopia and other Mediterranean countries.[2] The main goods that Egypt had to trade with were raw foodstuffs. Salt alone was too cumbersome to trade but salted foods were easier to trade with. Well-salted food such as fish does not spoil very easily. Egypt began trading salted foods for other goods on the Mediterranean market. The Roman Empire controlled the prices of salt as a means of gaining public support in times of crises. They would lower the price of salt so that the lower classes could afford the market price.  The Romans could raise money for the military by raising the price of salt and charging people who had limited access to salt a higher price. Salt was vital to the survival of the Roman Empire. Not only did the citizens of Rome need salt but also in order for the Roman army to continue its military campaigns it needed great quantities of salt  for its troops and animals.  Great roads, such as the Via Salaraia (salt road) were built across the Italian peninsula to ensure that goods would arrive as quickly as possible.

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Written by Alex Boyce, 2003