The Salt of The Earth 


Charlene K. Smith


This lesson was created as a part of the SMART website and is hosted by the Illinois Institute of Technology

The Salt of the Earth

  .  .Throughout  history, salt has always been a precious to man.  It was once traded for gold.  In the ancient days of the Bible the disciples were called by Jesus "the salt of the earth," and later carried out by the Romans, during baptismal ceremonies by placing a few grains of salt on the child's tongue.  The early Chinese used coins of salt and in Europe some Mediterranean people used cakes of salt as currency.  Roman soldiers were sometimes paid in salt.  The word "salary"  comes from "sal," the Latin word for salt. The main sources of salt in ancient times were dry coastal areas near the Mediterranean.  Early trade routes centered on Spain, Italy, Greece and Egypt.  Many of  the caravan trade routes were developed to transport salt, and Genoa, Pisa and Venice emerged as centers for the salt trade.                                                                                        

Throughout history, wars have been fought  over salt or lost for the lack of it.  During the Revolutionary War Benjamin Franklin made a secret deal with Bermuda to supply salt to the American forces. In 1783, after the Revolutionary war was won, salt works were set up along the Atlantic Coast.  Major salt deposits found near Syracuse provided one of the main reasons for the construction of the Erie Canal, which opened in 1825.


In Michigan, a huge sea covering the region evaporated more than 400 million years ago, forming salt deposits which were gradually buried by glacial activity.  This salt bed spreads over 170,000 square miles under Michigan, Ontario, Ohio, Pennsylvania, New York and West Virginia .  Some estimates suggest there is enough salt in the Metro Detroit underground to last 70 million years.    


What is sodium?  Who is in need of its valuable minerals? Why is stored in great abundance on the earth?  People, Plants and animals all need it.  I wanted to investigate why it was and is so important.    

Burial beliefs of Egypt 

A mummification is an ancient mysterious art. It was important because the ancient Egyptians believed in afterlife where the spirit, the ka, would return to the original body. The process of mummification took many years to perfect, probably a thousand years.

The whole process depends on desiccation. Bacteria and fungi, like all other living organisms, require water to survive. Therefore, if water is removed from the body, putrefaction will not occur.

Mummification was carried out in special places called "The House of the Dead." The morticians were qualified people who carried on this art. They were outcasts from the rest of the population, since people feared they that carried infections from dead people. The process of mummification took 70 days and was expensive. It was reserved for royalty and nobility.

The process began by laying the corpse on a table. An incision was made on the left side of the abdomen, and all the organs were taken out, but not the heart. The individual organs were wrapped in a cloth with natron salt and put in canopic jars (Fig. 1). Natron salt is a combination of sodium bicarbonate and sodium chloride, and was obtained from the Natron Valley in the Western Desert (Wadi El-Natron).


In Egypt natron played an important part in the burial  of the dead.  The entire process of mummification took as many  as 70 days.  The natron was placed in the cavities of the deceased which dried the moisture from the body. The important organs were removed and placed in canopic jars to be used later upon reincarnation. The body was then wrapped in linen strips with the enhancement of herbs and spices.   


Morton Salt Company and its importance in America

The history of the girl with the umbrella - When it rain its pours

Use, Misuse and Consequences of salt on streets

Student Assignment

Select one topic to investigate on the use of salt.

Answer the following questions.

1.  Where does salt come from?

2.  How is it made?

3.  Why is the ocean salty?

4.  Give 5 examples of salt being a useful product.

5.  Give 5 examples of salt being a harmful product

Demonstrate one experiment using the scientific principles of  inquiry.

Use show and tell method


Rubric (5 points) Teacher and student evaluation

1.   Did you complete 5 assignments?

2.  Did you  discover new facts about salt?

3.  How is salt helpful to us?

4.  How is it harmful?

5. Demonstrate your scientific inquiry to the class.

    What did you enjoy most about completing this assignment?




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