Page "Nautical mile" Paragraph 19

Use of angle-based length was first suggested by Edmund Gunter ( of Gunter's chain fame ).

During the 18th century, the relation of a mile of 6000 ( geometric ) feet, or a minute of arc on the earth surface had been advanced as a universal measure for land and sea.

The metric kilometre was selected to represent a centisimal minute of arc, on the same basis, with the circle divided into 400 degrees of 100 minutes.