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On 10/4/2016 2:13 PM, David Fleming wrote:
> Appologies to Gary and all Navlist members my previous reply was too
> terse and further should have been directed to Bill B.
>
> Google Earth claims1 degree longitude at 41 N represents .76 degree arc.
>  This is correct.
>
> GE also says the arc is 45.46 nm long.  therefore 45.46nm / 60 nm/degree
> = .7576 degrees.
>

Perhaps semantics.

To the best of my knowledge there are 360 degrees in a circle, 60
minutes per degree, and 60 seconds per minute.

Short answer, 86 degrees - 85 degrees = 1 degree, period.

I suspect you are comparing apples to oranges. Certainly the distance in
miles, meters feet etc. between meridians diminishes as the position
moves from the equator to the poles, but a circle created by a parallel
is still a circle (albeit with a smaller radius) and  degree remains a
degree (as do arc minutes and arc seconds relationship to a degree).

How then should I report my position on the 41st parallel half way
between the 85th and 86th meridian? As 85d 22' 44" given your assertion
that a degree is "45.46nm / 60 nm/degree = .7576 degrees" which equals
45'27". (45' 27"/2 = 22' 44").

I would prefer to report my longitude as 85d 30', especially if in need
of rescue (perhaps lost in a sweetcorn maze?)! Less terse, but IMHO a
superior answer if you want a chopper to show up with boiling water and
butter :-)

   

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