Longitude

[Bruce Appelbaum]

     1.  A nautical mile is a bit more than 6076 feet, while a statute mile 
     (the landlubbers version) is 5280 feet.  Of course, there is also a 
     British nautical mile, equivalent to 6080 feet.  I guess if they had a 
     mile in China it would be very small, especially if it had been based 
     on a bound foot.
     
     2.  Don't know why there is a different unit on land and sea.  
     Probably the same reason why Imperial (British/Canadian) gallons are 
     equivalent to 1.2 US gallons.  Or why there are troy ounces (used in 
     metal industry) and avdp ounces (conventional measurement).  Just 
     something that developed over time.
     
     3.  There is no metric equivalent to a nautical mile (nautical km) -- 
     one of the purposes of the metric system is to have single units of 
     length, mass, etc.


______________________________ Reply Separator _________________________________
Subject: RE: Longitude
Author:  Joe Varo <vjvaro at erie.net> at Internet
Date:    4/10/97 11:49 AM


Just finished the book.  It's a short, quick, easy read which just give an 
overview on the difficulties of determining longitude for sea navigation. 
Apparently latitude was rather easy to determine, but not so with 
longitude.  Also deals with the politics involved in a contest established 
to invent the first reliable method of determining longitude.
     
By the way, can anyone tell me what the difference is between a "mile" and 
a "nautical mile".  This is something I've always wondered about but have 
never been able (or willing to look hard enough) to find a satisfactory 
answer.  I know there's a conversion formula for miles to naut. miles, but 
what is the purpose of the difference?
     
Is there a metric equivalent, like a "nautical kilometer" or something?
     
Joe