Dave Bell <[EMAIL PROTECTED]> writes:

> I'd call it a fairly expensive joke!
> 
> Note that a "real" dial should, roughly speaking, have the hours from 0600
> to 1800 in a semicircle, running from East through North to West (in the
> northern hemisphere). This is a clock face, with only room for 12 hours in
> a day!

The sundial at
http://www.shopoutdoordecor.com/cgi-local/SoftCart.exe/online-store/scstore/p-AWS209S.html?L+scstore+wxsc3599ff367336+981445839
is certainly poorly (criminally?) designed in that it gets out of
whack as the declination changes (by about +/- 1 hour, even if
properly mounted).  The simple fact that there are only 12 hours in a
circle does not, however, make it totally useless.  Since the foot of
the gnomon is on the circle rather than in its center, the shadow
falls at about the right spot near sunrise and sunset.

In fact, if the circle were either perpendicular to the gnomon or
elongated to an ellipse along the 6-12 axis, it could be turned into a
perfectly fine sundial.

In the "Sundial Installation Instructions", the company states, "These
sundials are designed for ornamental use and give an approximation of
time. As a very accurate sundial would require constant adjustment and
less ornamentation, these models have been selected to give years of
enjoyment without the aggravation of constant tuning."  I find these
words rather painful, knowing that sundials certainly can be accurate
(limited in most cases by the Equation of Time), and having seen many
examples of the beauty the artisans of this list can bestow on such an
accurate dial.

--Art Carlson

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