Can you answer this old riddle? Throw this rock into the water and it changes into water. What is it? Salt! Dry salt is a rock. In water it dissolves, breaking apart until you can't see it. Most salt comes from oceans, other salty water, and places where salt water has dried. If all the oceans’ salt were piled on top of the United States, we would be covered in salt a mile high!
In your body right now, you have about 3 ounces (85 grams) of salt. That is the same amount as 98 small salt packets given away at fast-food restaurants! We need salt to live. However, if we have too much, it is bad for our health. When we cry, sweat, or go to the bathroom, we lose salt. We make up for what is lost by eating food with salt in it.
Today, salt is easy to find. Long ago, it was often hard to locate salt lakes or rock salt that could be dug out of the earth. People even looked for spots where ocean water could evaporate, or turn into air, leaving only salt. One of the oldest salt mines is below Hallstatt, Austria. The name Hallstatt means, “salt town.” Salt has been mined there for almost 3,000 years.
Long ago, people salted meat and fish to keep them from turning rotten. As a result, they needed lots of salt. They called it white gold because it cost as much as gold. The ancient city of Rome, Italy, had its start as a place to buy and sell salt. Part of a Roman soldier's pay, or salary, was given to him in salt. Our word “salary,” comes from the Roman word, “salarium,” meaning, “salt money.”
The ancient Maya of Central America made salt in drying ponds near the ocean. They also heated salt water in pots until the water was gone, or evaporated. They used salt for many things besides eating. When a child was born, the parents tasted holy salt and sprinkled it inside their house. Soldiers' jackets were stuffed with salt to make them hard enough to stop arrows. They also offered salt to their gods as food.
Salt at the End of the World
Joined by his father and uncle, Marco Polo traveled from Italy to the Kavir salt desert of Iran. Few had ever crossed it. Most Italians thought the Kavir was the end of the world. Crossing the desert was hard. Salt broke under their feet, making it tough to walk. Water was too salty to drink. After about two weeks, the Polos reached the end of the desert. Back in Italy in 1297, Marco Polo made a book about his journey to the Kavir and beyond.
For hundreds of years, most French people had to pay salt tax—extra money to the king every time they bought salt. This tax was famous for being unfair. Kings ordered some people to buy lots of salt and pay high taxes. Others paid no tax and could buy as little as they wanted.
The salt tax was one of the reasons people fought in the French Revolution in 1789. This war ended the rule of kings in France.
The people of India were ruled by England, but they wanted to rule themselves. In 1930, Mahatma Gandhi, a famous Indian leader, led a march to the sea. His march was a protest against English rule.
After walking 240 miles, he gathered salt on the beach. It was against the law at that time to gather salt. England controlled all of India's salt and forced India's people to pay a salt tax. This protest and one held later at a salt factory helped India become free to rule itself.
Today nearly every table has a salt shaker. Salt is no longer as costly as gold. It is so cheap people often give it away for free. We still love salt, however. We use it in countless ways. Only five salt grains out of 100 are for food. People use salt to melt ice from roads. It is an ingredient in paints, glues, medicines, and more.