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    Re: Showing a Mercator Projection is not a perspective projection
    From: Robin Stuart
    Date: 2016 Dec 31, 11:39 -0800


           The problem you are wrestling with is precisely the reason why I suggested that the bladder sticks to the inside of the cylinder. For a given parallel at latitude L to touch the cylinder it needs to expand by a factor sec(L). When it touches it sticks and is prevented from expanding further. This locks in the scale factor for that location which then varies continuously with latitude. It is not allowed to creep up the wall as further expansion occurs. The total vertical extent would be found by integrating sec(L). I think that this model does the trick but might have missed something.

           The description of Wright’s model in the paper Frank provided is rather terse and I have yet to find it in Certaine Errors where he presumably provides all the details.

    Robin Stuart

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