fog signal

noun
1.
any of various types of signal used as a warning by vessels navigating in fog or mist.
Origin
1750-60
Examples from the web for fog signal
  • Every fog signal station sounded its own distinctive pattern so that captains could pin-point their position.
  • The same construction crew that built the tower and the fog signal built it.
  • Attached to the light tower is a fog signal building consisting of a brick structure with a gabled roof.
  • There are other historic structures on site, including an oil house and a fog signal area.
British Dictionary definitions for fog signal

fog signal

noun
1.
a signal used to warn railway engine drivers in fog, consisting of a detonator placed on the line
Encyclopedia Article for fog signal

sound or light signal emitted in fog or mist by lighthouses and buoys to indicate a shoreline, channel, or dangerous stretch of water and by vessels to indicate their position. Each signal has a distinctive code. All vessels, whether stationary or moving, are required by law to utilize fog signals in inclement weather; the type, number, length, and timing of the signal indicate the size of the vessel and its position. The nature and application of fog warnings is codified in the International Regulations for Preventing Collisions at Sea (commonly called International Rules of the Road), applicable to all international waters. The earliest sound signals were made by bells, gongs, and explosives; these largely have been replaced by foghorns powered by compressed air or electricity. See also lighthouse.

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