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
Lease automatic custody transfer unit Lease automatic custody transfer unit A Lease Automatic Custody Transfer unit or LACT unit measures the net volume and quality of liquid hydrocarbons. A LACT unit measures volumes in the range of 100-7000 BOPD. This system provides for the automatic measurement, sampling, and transfer of oil from the lease location into a pipeline. A system of this type is applicable where larger volumes of oil are being produced and must have a pipeline available in which to connect. American Petrolum Institute (May 1991), Manual of Petroleum Measurement Standards, Chapter 6, Section 1, Lease Automatic Custody_Transfer (LACT) Systems, Second Edition. American