The foghorn or siren
The sailor on the watch would go to the prow and activate the siren. In order to do this, one needs to pull up and down a lever attached to a bellows. The bellows blow air into the brass cone, thus producing a sound. The standard timing for the foghorn is 5 sounds every 60 seconds, or 5 sounds every 90 seconds. There are several types of foghorns: foghorns in mahogany case, in brass cylinder with piston, etc. They were used on old tall ships until the mid 1900s.