Ann Margaret Kennedy, age 15, of Nogales, Ariz., for her question:
HOW OLD IS THE PRACTICE OF MEDICINE?
Medical practice goes back to prehistoric times. Probably the first surgical treatment was an operation called trephining. Trephining involved the use of stone instrument to cut a hole in a patient's skull. Scientists have found fossils of such skulls that date back more than 10,000 years.
Prehistoric man may have performed the trephining operation to release spirits believed responsible for headaches, mental illness or epilepsy. But trephining could have brought relief in some cases.
Until the early 1900s, surgeons practiced trephining to relieve certain types of pressure on the brain.
We also know that prehistoric man probably discovered that many plants can be used as drugs. The use of willow bark, as an example, was used to relieve pain for thousands of years. Today, scientists know that willow bark contains salicin, a substance related to the salicylates used in making aspirin.
By about 3,000 B.D., the Egyptians had developed one of the world's first great civilizations and invented one of the first systems of writing. Shortly after 3,000 B.C. they also began making important medical progress. Much of our knowledge of this progress comes from ancient Egyptian manuscripts.
The world's first physician known by name was the Egyptian Imhotep, who lived about 2,700 B.C. He was later worshiped as the god of healing.
About 2,500 B.C., Egyptian physicians started to specialize. They produced a textbook that told how to treat dislocated or fractured bones, external abscesses, tumors and wounds.
The ancient Hebrews made progress in preventive medicine from about 1,200 to 600 B.C. They required strict isolation of persons with contagious diseases.
The ancient Chinese developed medical practices that have been handed down almost unchanged to the present day. This traditional medicine is based on the belief that two life forces, Yin and Yang, flow through the human body.
Disease results when the two forces are out of balance. To restore the balance, the Chinese began the practice of acupuncture, which is the inserting of needles into parts of the body thought to control the flow of Yin and Yang. Chinese docotrs still practice acupuncture.
After about 800 B.C.,,Indian physicians became famous for their surgical skills.
The civilization of ancient Greece was at its peak during the 400s B.C. Throughout this period, sick people flocked to temples dedicated to the Greek god of healing. At the same time, a great Greek physician named Hippocrates began showing that disease has only natural causes. He became the first physician known to consider medicine a science, separate from the practice of religion.
After 300 B.C., the ancient Romans made strides in public health when they built acqueducts that carried 300 million gallons of fresh water to Rome each day. They also built an excellent sewage system in Rome.