FOR WHOM DID THE HORNS BLOW? A ship's whistle is one of the oldest devices used by mariners to alert of a specific situation. To be exact, for communicating passing intentions (one short blast means "let's meet port to port", two "starboard to starboard", and so on). But before ships were equipped with modern whistles or horns, these were already an integral part of some lighthouses and sea buoys to aid mariners navigate. It is a fact that sound travels more efficiently across fog and heavy rain. Sound is more effective than light when navigating in reduced visibility. With all the technological advances, such as the AIS, the whistle of a ship is rarely used these days. Rule 35 of the International Regulations for preventing collisions at sea (COLREGs) prescribes the sound signals given by ships in or near an area of restricted visibility. However, the ship's whistle is sometimes used unofficially to mark a