Definition, history and etymology of the bell
The term "bell" derives from Campania, the region where bells were first used for ritual purposes.
Bells are instruments made in the form of hollow vessels, generally of metal, but often also of wood, glass or terra cotta. They can be classified as idiophonic (instruments where the vibrating body is the same as the instrument) or, more simply, as percussion instruments.
Its vibrations are greatest at the edges and diminish towards the top of the cap.
There are two types of bells: those equipped with an internal striker (the common type in the West) and those that are struck from the outside with a "mallet" (the classic oriental bells). The shapes of bells vary depending on their cultural context, their use and the materials used to make them.
In general, large bells with strikers are cast in bronze (a copper-tin alloy) and are anchored to an iron structure called the castle; this type of bell is usually installed in the "belfry" of bell towers or civic towers.
Bells can have different diameters, from a few centimeters to several meters "The Tsar Kolokol" is the largest existing bell, and measuring almost seven meters in diameter (diameter 6.82 m, height 7.47 m, thickness 0.49 m) it is the largest bell of a concert of great bells, dating from 1817, installed in the Kremlin that now, being broken, is on display in Moscow's Red Square.
Their are, however, also small table bells, often made of silver and artistically decorated, equipped with handles, generally used to command attention, at the table to call servers or, sometimes, during mass, to indicate the moment of the elevation of the host and when the faithful should kneel and rise according to the liturgy.