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    Re: dip, dip short, distance off with buildings, etc.
    From: Bill B
    Date: 2006 Jan 8, 01:24 -0500

    Bill, you wrote:
    "I let go of your Chicago  observations"
    Frank replied:
    "They're not dead yet!"
    Great!  Rather than pay sleuth working backwards from your estimate of
    horizon distance of 4-5 miles (statute for Lake Michigan charts, or nautical
    miles?), do you recall an approximation of your height of eye for the beach
    shots?  If so, may I subtract appropriate dip from the sextant readings?
    "Just today, I finally got  around to measuring the heights of the towers in
    question above lake level..."
    And? Drum roll please...
    Now IF the nice tour-guide ladies on the river architectural cruise are
    correct, lakefront real estate was basically a landfill after the Chicago
    fire (and Louis Sullivan was a form-follows-function architect?). And given
    the Chicago River is higher than lake level, coupled with empirical
    observations, the "base" of the buildings in question should be 30-40 ft
    above nominal lake level.  No accounting for which level of a multi-level
    city the base is on, or burms and drainage consideration.  So give!
    Inquiring minds want to know. 

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