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    Re: Bermuda to St Helena on a North Atlantic Mercator Chart
    From: Frank Reed
    Date: 2021 Dec 25, 11:58 -0800

    David P., you wrote:
    "I believe I can do the whole trip there and back on one North Atlantic (Southern Section) Mercator chart"

    Are you talking about the reflection symmetry of a great circle? In the sense that if I have points for a great circle curve north of the equator, I can use them for an extension south of the equator by flipping and mirroring? Are we assuming that you have a set of overlays, like the ones in the attached images to determine points on a great circle?

    Frank Reed
    Note: The attached plots and overlays use a simple rectangular projection. They could, of course, be drawn and used similarly for other projections.

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