altitude of the arms above the ground. With this in mind, perhaps a
fan-out of marks and associated hour lines for various heights to
account for children of different ages. This could be an attractive
display on the ground. Maybe different colors for different gnomon
heights. As a younger child grew, he/she could progress to the "taller"
sets of marks and hour lines.
Tom Egan
33.642N 117.943W
Willy Leenders wrote:
Douglas,
The sundial can be reduced to a mark on the playground where a person has to
take place, an indication for the direction the person has to strech out his
arms horizontally and the corresponding hour-lines.
Willy Leenders
Hasselt, Flandern in Belgium
50,9 N 5,4 E
Douglas Hunt wrote:
Can any of our Mailing-List experts suggest some horizontal sundial design
suitable for locations almost on the Equator, (actually 2 Degrees North) ?
We have been contacted by a school in Singapore, who would like to install
a large playground sundial - BUT ideally having nothing above ground-level
to cause any 'accidents', or increase the cost/complexity of their layout.
They want to avoid a 'gnomon' obstructing vehicles in the playground area.
They had initially thought of using a traditional "analemmatic", but those
are not really suited to locations within the 'tropics' (because the Hour-
markers will interfere with the central Date-scale). We recommended using
a 'door-frame polar' design, as being the most popular for schools near to
the Equator (i.e., two upright supports with a near-horizontal North/South
cross-piece, the shadow of which tells time on Hour-lines painted on their
playground) - but they prefer an entire layout on the ground, if possible.
I will be very grateful for any suggestions, as to whether there is a type
of sundial which could be installed at a near-Equator location - and which
does not need a 'gnomon' (apart from maybe a person!), above ground-level.
Douglas Hunt.
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