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    Re: Near-pole CN? Transverse Mercator?
    From: Frank Reed
    Date: 2019 Oct 3, 09:27 -0700

    I wrote:
    "You don't need the Transverse Mercator projection for anything except understanding certain old standards for mapping applications."

    And David, you confirmed what I said when you wrote:
    "Please don’t tell the UK’s Ordnance Survey.  Nearly all their large scale maps are developed from a transverse Mercator projection around the 2W meridian with a datum based upon the Airy 1830 ellipsoid, a projection particularly suited to long thin countries.  They still sell millions of paper copies a year as well as producing digital versions."

    The Ornance Survey is a "British institution" which is a wonderful thing and also a burden. The OS map-makers can barely sneeze without getting complaints that they're desecrating hallowed tradition. 

    Little-known fact: Queen Boudica herself drew the first Ordnance Survey map and decreed that it must use the Transverse Mercator projection (known as the Longways Icenian projection back then)  and not that Roman Imperial projection. Did she know why her Druids had recommended it? No, it was a mystery to her and remains a mystery today. But the projection has been forever enshrined in the Deep Lore of the Ordnance Survey as the the One True British Projection (despite having that Flemish guy's name in it).

    To clarify what I said originally a bit, from the perspective of navigation, the Transverse Mercator projection has a seductive and misleading name (hence "clickbait"). It is a projection with math that is abstractly identical to the standard Mercator projection, but the initial conditions of the projection are so different that most of the properties navigators have learned to associate with Mercator projections disappear. Its value is historical.

    Frank Reed
    Boudica's connection to Brexit. Seriously?? (read this a month ago and thought "this article borders on being clickbait!")

       
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