Bells are idiophones (instruments sounding the vibrations of resonant solid material). Early bells were cast from metal in the Bronze Age. The Chinese culture took the bells to a more sophisticated level. During the European Middle Ages, Christians used bells to signal divine services. The origin of bells in Christian worship can be traced back to the dinner bell in the Old Testament. There were pictures of bells on stone tablets dating back to the 5th century BC.
All cultures use bells and many have a major significance and reflect the history and culture of the people. In the United States, the Liberty Bell is a symbol of freedom and independence. School bells symbolize freedom to pursue education. Garden bells can offer romance and atmosphere any time of the year.
Farm bells have been used for centuries to summon family and farm workers from the fields for dinner and also to alert people in times of emergencies or danger. The sound of this bell was not gentle: it was very resonant and usually of a fairly good size.Not only is a bell on a ship used as a dinner bell but it also serves as a warning to other vessels when the visibility is not good (in fog for example). In 1858, British Naval Regulations made it mandatory that ships ring their bells in inclement weather. Today, maritime law requires all ships to carry a working bell. In 1798, Paul Revere made a bell weighing 242 pounds for the frigate Constitution known today as "Old Ironsides".