Ship's bell

A ship's bell is used to indicate the time aboard a ship and hence to regulate the sailors' duty watches. The bell itself is usually made of brass or bronze and normally has the ship's name engraved or cast on it.

The classical system was:
 * † British usage after the Nore mutiny
 * ‡ Before the introduction of time zones, noon was not struck by the glass, but when the captain or officer of the deck confirmed local noon by the sun, using a sextant.