When the crew first came on board they were split into two shifts. These were called the port and starboard watches after the two sides of the ship.

Each man had a partner on the other watch that he shared his sleeping space (and probably his lice and fleas) with.

The time of the watches was measured with a sandglass and the bell was rung once every half hour.

Since the watches lasted for four hours there were eight bells in a watch.

Sailors were punished for sleeping on their watch!