fog bell

Both vessels were proceeding slowly and ringing fog bells.

Around 1851, mechanically rung fog bells were introduced.

Across the water, unseen through that featureless dark, the fog bells of Werpoint pealed the alarm.

One of the first automated fog bells was the Stevens Automatic Bell Striker.

Some later fog bells were placed under water, particularly in especially dangerous areas, so that their sound (which would be a predictable set, such as the number "23") would be carried further and reverberate through the ship's hull.

On August 3, 1846, the City of Dublin Steam Packet Company's paddle steamer Prince ran into the cliffs about 2 km north of Baily in heavy fog, and as a result it was decided that fog bells should be installed at the lighthouse.