Unlike civil clock bells, the strikes of the bell do not accord to the number of the hour. Instead, there are eight bells, one for each half-hour of a four-hour watch.
The classical system was:
|Number of bells||Middle|
The hours between 16:00 and 20:00 are so arranged because that watch (the "dog watch", which is cur-tailed) was divided into two. The odd number of watches aimed to give each man a different watch each day.
Some domestic "ship's bell" clocks use a simpler system:
|Number of bells||Hour (a.m. and p.m.)|
The number of bells may be used to refer to the hour so indicated.