Nautical mile 1 sea mile", followed by "For most practical purposes distance is measured from the latitude scale, assuming that one minute of latitude equals one nautical mile". One tenth of a nautical mile is a cable length. The derived unit of speed is the knot, defined as one nautical mile per hour. The metre was originally defined as of the meridian arc from the North pole to the equator passing through Dunkirk. The Earth’s circumference is therefore approximately 40,000 km. The equatorial circumference is slightly longer than the polar circumference – the measurement based on this (40,075.017 km x x =
Foul (nautical) HRH Prince Philip, The Duke of Edinburgh, and is flown on the ship carrying the monarch to sea. It is also flown during the launching of a warship of the Royal Navy. The fouled anchor is also depicted on the emblem of the U.S. Public Health Service. Ships would display a fouled anchor to indicate to officers on shore that sick persons were onboard, prompting further investigation and possible quarantine. The term can be applied to many nautical situations: Foul (nautical) Foul is a nautical term meaning to entangle or entwine, and more generally that something is wrong or difficult.