Imagine that you could step through a time portal and get a firsthand look at what daily life in ancient Egypt was like. For decades, archaeologists
have been taking just these types of journeys, and their tour guides have been the mummified remains of individuals who died centuries ago. Even though their lips are silent, mummies speak volumes to those who know how to ask the right questions. When most people hear the word "mummy," they usually think of ancient Egypt. But mummies have been found all over the world, including China, Europe, Peru, and Mexico. In fact, many mummies have formed naturally without any human preparation at all. For mummification to occur, all water must be removed from the body. Little or no decomposition from bacterial action can take place. As you might expect, most mummies have been discovered in desert environments. But they have also been found in peat bogs, where the water is extremely acid and has little or no oxygen, and in the tundra, where individuals have become trapped in glacial ice. In both environments, bacteria cannot break down the body tissue. Some scientists argue whether "bog men" and "ice men" are true mummies, but these bodies still can reveal a great deal about the world they lived in. The earliest Egyptian mummies date back to around 3200 B.C. By interpreting the text on the walls of tombs, scientists have learned that the mummification process evolved over time. In early days, preparers would simply treat the body by covering it with a natural salt, called natron (now called baking soda), to help dry it out, and then wrap it in bandages soaked in a type of resin. By about 1500 B.C., the art of mummification reached its peak. Before treating the body, morticians would remove the brain and many vital organs. Then they would pack the abdominal cavity with natron, sand, or sawdust and immerse the body in more natron for about 40 days. After that, the body was washed, repacked with spices and more natron, and wrapped in bandages. The whole process took about 70 days. People were often buried with food, tools, jewelry, clothes, and even pets. By studying these artifacts and using modern-day clinical analysis on the mummies, scientists have unlocked many mysteries about diet, health, and even grooming habits. With the help of CAT scans, X rays, MRIs, and other clinical techniques, these silent sentries of past civilizations tell us much about how they lived.
Discover how you can make your own mummy. Have you ever wondered why every time you eat salty foods, you get thirsty? Or why fresh vegetables tend to shrivel up when you sprinkle salt on them? The answer is simple. Salt is a desiccant - it helps remove water from things, including human bodies. In this activity, you will experiment with different salt compounds and discover which makes the best mummified apple. Materials
- 2 fresh apples
- large box of table salt
- large box of Epsom salts
- large box of baking soda
- eight 12-oz disposable plastic cups
- measuring cup
- large mixing bowl
- permanent marking pen
- roll of masking tape
- sensitive balance or food scale
- piece of graph paper and pencil
- Slice the two apples into quarters so that you have eight slices similar in size. Place a piece of tape on each cup and write the words "starting weight." Select one slice, weigh it, and record the weight on the outside of cup 1. Follow the same procedure with the other seven apple slices until each cup has been labeled with the appropriate starting weight.
- Add exactly 1/2 cup of baking soda to cup 1, making sure to completely cover the apple. Write the words "baking soda only" on the outside label. Fill cup 2 with 1/2 cup Epsom salts. Fill cup 3 with 1/2 cup table salt. Make sure you label each cup.
- Repeat the same procedure for cups 4-6 using a 50:50 mix of Epsom and table salts in cup 4, 50:50 mix of table salt and baking soda in cup 5, and a 50:50 mix of baking soda and Epsom salts in cup 6. Again, make sure each cup has the correct label.
- In cup 7 make a mixture of 1/3 baking soda, 1/3 Epsom salts, and 1/3 table salt. Leave cup 8 alone as a control. Place the cups on a shelf out of direct sunlight and let them sit for seven days. After a week has gone by, take out each apple slice, brush off as much salt as possible, and reweigh. (Do not rinse the apple off because that will rehydrate it.) Compare the starting and ending weights of each slice and calculate the percentage of weight which is moisture lost for each by dividing the difference in weight by the starting weight. Questions 1. Which compound would seem to work best at making an apple mummy? 2. Would you have achieved the same results if you used a whole, unpeeled apple? Try it and find out. 3. What was the point of leaving one of the apple slices in a cup without any salt at all? 4. Where did the moisture in the slices go? How could you confirm this?