Earth's circumference mile in the seventeenth century and the metre in the eighteenth. Earth's polar circumference is almost exactly 40,000 km because the metre was originally calibrated on this measurement (1/10-millionth of the distance between the poles and the equator), which is almost exactly 21,600 nautical miles (being defined as one minute of a degree – i.e. 360 multiplied by 60). It has been described as "the single most important measurement" of the Earth, assuming the Earth to be a sphere (the Earth is an technically an ellipsoid, albeit with just 0.3% flattening). Earth's circumference lines are the foundation of the coordinate
Units of measurement in France before the French Revolution (league) had a number of variations, particularly the "aune" (which was used to measure cloth The "loi du 19 frimaire an VIII" (Law of 10 December 1799) states that one decimal metre is exactly 443.296 French lines, or "3 pieds 11.296 lignes de la "Toise du Pérou"". Thus the French royal foot is exactly 9000/27,706 metres (about 0.3248 m). In Quebec, the surveys in French units were converted using the relationship 1 "pied" (of the French variety, the same word being used for English feet as well) = 12.789 English inches. This makes the Quebec "pied" very slightly smaller (about