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    Comparing Watch
    From: Bill Murdoch
    Date: 2000 Feb 04, 6:28 PM

    On page 324 (figure 18-9) of Richard Hobbs, "Marine Navigation", 4th edition
    is a picture of a "comparing watch".  It is a mechanical stopwatch-like
    watch.  There are the usual hour, minute, and second hands of a pocket watch
    and in addition an extra second hand mounted on the center shaft of the
    watch.  According to the text, pushing the button atop the watch stops the
    extra second hand so that the exact time that the button was pressed can be
    read.  The watch is especially useful in timing sextant sights.
    I have never seen a watch like this before.
    Several years ago I looked without success for a digital stopwatch which
    would indicate GMT hours, minutes, and seconds and the display of which could
    be stopped, read, and resumed.  I never found one.  I resorted to taking a $6
    digital stopwatch from Wal Mart and modifying it to make it something like
    the watch I wanted.  I put the it into the stopwatch mode and started it
    timing at midnight GMT.  Then I removed the plastic button that changes the
    mode of the watch and the plastic button that starts and stops the stopwatch
    to keep from accidentally pressing them.  That left the lap button.  When
    pressed once the watch freezes.  When presses a second time the watch resumes
    displaying the time since midnight in hh:mm:ss format.  That works all right,
    but I can only correct any watch error at GMT midnight.
    Does anyone know of a currently manufactured "comparing watch" either
    mechanical like the one in the figure or a digital ?
    Bil Murdoch
    Kingsport, TN

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