Vincent Santeramo, age 10, of Chisholm, Minn., for his question:

WHY DO BELLS SOUND DIFFERENTLY?

Bells have been known to exist since 800 B.C. A ceremonial Assyrian bronze bell from this date has been found, and it is known that the Chinese from this time also used bells. The ancient Greeks used bells to announce all important events.Tones vary in bells from a very high pitch to a low one, according to their thickness and the size. Sets of bells can be made so that each one has a different tone to correspond with the tones of a musical scale. A player can then strike one after another to play a tune.

There are many sets of carillon bells in almost every country of the world that are operated by electricity. Some have 70 or more bells, each one cast to produce its own separate tone.