Doug O'Dell, age 11, of Newport News, Va. , for his question:

Why are there snakes on the doctor's emblem?

This emblem is called the caduceus, and it originated 'way back when people believed in gods and goddesses. From time to time, these super humans sent messages to each other and to the ordinary folk. The herald whose job it was to carry these special messages was the god Mercury, also known as Hermes. He carried a caduceus as a staff or herald's hand .

It is thought that originally the caduceus of :Mercury was made of olivewood and twined with garlands. Later the garlands were replaced by a pair of snakes, perhaps because in those days the snake was a symbol of wisdom. To speed him on his way, Mercury had little wings on his feet and on his hat. Another pair of wings was added to his staff. Later, the caduceus with its wise snakes and swift wings became a medical symbol and the emblem of the Medical Corps of both the U.S. Army and Navy.