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    Re: Distance off useing a hand held compass
    From: Richard M Pisko
    Date: 2003 Mar 25, 14:06 -0700

    Back before the dawn of time (on Tue, 25 Mar 2003 12:06:12
    -0800, to be exact), "Royer, Doug" 
    >5. Work the equation and the result will be the distance off the object.
    >Hopefully this diagram will be transmitted better than the one yesterday.In
    >fact if this diagram goes through it was basically the same set-up as
    >yesterday's diagram.
    The 1911 Encyclopedia mentioned yesterday for telegraph
    cables wrote about a similar system double sighting system
    under "rangefinder".  There was mention of a 50 yard cord
    for a base line, two people, and two sextants held
    horixontally.  One was fixed at 45 degrees, and the other
    read the angle ... which I think may have had a special
    spiral scale on a micrometer drum so as to read directly in
    yards.  To bad the encyclopedia on line doesn't show
    illustrations to match the descriptions.
    One apparent problem was making sure both observers merged
    the same target object with the split image of the other
    observer's sextant.
    However, I thought you mentioned a military compass, which
    is graduated in mils in the US.  Could you not just take a
    bearing, walk away from that point so as to keep the object
    more or less at right angles to your (perhaps slightly
    curved) path, and stop when the new bearing is 10 mils
    different from your first?  That way, the distance to the
    object will be 100 times the distance you traveled ...
    barring local magnetic anomalies.
    Just a thought.
    Richard ...

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