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 =
240 mm howitzer M1 240 mm howitzer M1 The 240 mm Howitzer M1, popularly nicknamed the "Black Dragon", was a towed howitzer used by the United States Army. The 240 mm M1 was designed to replace the World War I era 240 mm Howitzer M1918 which was based on a 1911 French design and was outdated by World War II. The project to replace the M1918 began in 1941. The 240 mm howitzer was the most powerful weapon deployed by US field artillery units during World War II, able to fire a high explosive projectile 25,225 yards (23 km). It was the largest field