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
USS Wissahickon (SP-852) was under the command of Lieutenant, junior grade, E. W. Haskell, USNRF on that date - but one secondary source states that she was not commissioned until 3 October 1917. At any rate, "Wissahickon" was commissioned sometime between April and early October 1917. Sources differ as to whether she was commissioned without her name as USS "SP-852" or as USS "Wissahickon" (SP-852), with her name being changed in 1918 to USS "SP-852". The Navy considered "Wissahickon"/"SP-852" too light for "distant service" in European waters, so she was placed in the Naval Coast Defense Reserve and assigned to the 1st Naval