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    Further on Datum Shifts From Bowditch
    From: John Kabel
    Date: 2002 Jan 18, 7:04 AM

    In the 1995 Bowditch, section 211, it says, referring to the
    replotting of positions from one chart to another, with a datum
    "These datum shifts are not constant throughout a given area, but
    vary according to how the differing datums fit together.  For
    example, the NAD27 to NAD 83 conversion results in changes in
    latitude of 40 meters in Miami, 11 meters in New Yourk, and 20 meters
    in Seattle.  Longitude changes for this conversion are about 22
    meters in Miami, 35 meters in New York, and 93 meters in Seattle."
    There is no mention of a "1 mile" datum shift between NAD 27 and NAD
    83.  That would be very surprising if it were true, as the only shift
    of that magnitude I am aware of is the NAD 27 to TOKYO datum shift.
    John Kabel
    In around 43 N, 81 W
    London, Ontario

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