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> Here's a puzzle: can you modify the Boy Scout watch method so that it
> does not confuse azimuth with local hour angle and thus becomes a
> somewhat more accurate compass?

How about this procedure:  Point the hour hand directly at the Sun
(in general this requires tilting the watch into the sky).  Rotate
the watch around its hour hand (which remains pointing at the Sun)
until 12:00 is also pointing into the sky at the same altitude (but
generally in quite a different direction).  Now the face of the watch
points north (in most of the northern hemisphere).

If the watch reads local apparent time and the sun is over the equator,
the only errors are caused by imprecision of pointing, though they may
be greatly magnified by the geometry.  Corrections for daylight savings,
longitude within zone, and equation of time are obvious, though perhaps
only the first is worthwhile.  It's not clear what, if anything, needs
to be done about declination.

Is this the kind of procedure Frank is envisioning?  Has he tried it?
        -- Bill

   

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