Greetings, fellow dialists,

A kind BSS member has given me a sundial.  It is made of cardboard and
is about 15 cm high.  He writes: I am enclosing a dial sun-compass which
may be new to you.  The principle was described in an article by Fred
Sawyer (Bulletin, British Sundial Society, 91, 3).  The device should be
assembled, using the card wedges to hold the two semicircles at 55 deg.
(my latitude) with June-July at the upper edge.  The bottom of the V
should coincide with the date.  Each arm casts a shadow to tell solar
time on the inner and outer scales.  When the dial is placed on a
horizontal surface so that the two times are the same the plane of the
vertical card coincides with the meridian.  Invented in 1664 according
to Sawyer.

I assembled it and it works!  The dial plate is at 55 deg. to the
horizontal, two gnomon edges cut out of a single card are at right
angles to each other and each is at 45 deg. to the dial plate.  The
whole thing has the feel of a tilted analemmatic dial with two oblique
gnomons.  The dial plate and upper gnomon are said to equate to Gordon
Taylor's large Royal Observatory dial now in Cambridge.  I only sort of
see how it works despite Fred Sawyer's benign instruction.  Can anyone
provide a few simple words to help me further?

Thanks in advance, Frank.

-- 
Frank Evans

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