Editing Geographical mile (section)

==Historical units==
Historically, certain nations used slightly different divisions to create their geographical miles.

The [[Portuguese units of measurement|Portuguese system]] derived their miles ({{lang|pt|milha geográfica}}) as one third of [[Portuguese league|their league]] of three separate values. When each equatorial degree was divided into 18 leagues, the geographical mile was equal to {{sfrac|1|54}} degree or about {{convert|2.06|km|mi}}; when divided into 20 leagues, the geographical mile was equal to {{sfrac|1|60}} degree, approximating the values provided above; and when divided into 25 leagues, the geographical mile was equal to {{sfrac|1|75}} degree or about {{convert|1.48|km|mi}}.

The geographical miles of the traditional [[Dutch units of measurement|Dutch]] ({{lang|nl|geografische mijl}}), [[German units of measurement|German]] ({{lang|de|geographische Meile}} or {{lang|de|Landmeile}}), and [[Danish units of measurement|Danish systems]] ({{lang|da|geografisk mil}}) all approximated their much longer miles{{mdash}}equivalent to English leagues{{mdash}}by using a larger division of the equatorial degree. Instead of using one minute of arc, they all used four{{mdash}}{{sfrac|1|15}} degree{{mdash}}to produce a distance now notionally equal to {{convert|7408|m|ft}} but actually differing slightly depending on official measurements and computations. (For example, the Danish unit was computed as equivalent to about {{convert|7421.5|m|ft}} by the astronomer [[Ole Rømer]].)<ref>{{cite journal|last1=Rabounski|first1=Dmitri|title=Biography of Ole Rømer|journal=The Abraham Zelmanov Journal|date=2008|volume=1|page=2|url=http://zelmanov.ptep-online.com/papers/zj-2008-b1.pdf |archive-url=https://web.archive.org/web/20110715130250/http://zelmanov.ptep-online.com/papers/zj-2008-b1.pdf |archive-date=2011-07-15 |url-status=live|access-date=1 February 2018|ref=ISSN 1654-9163}}</ref>