Dear Friends,
I seem to have talked myself
into making a dial in The Gambia, about 13° north of the Equator. The
design is fairly straight forward. In brief it is to sit on the ground on
the south side of the swimming pool at the hotel. It will recline so as to
be visible from the north from a lying position around the pool. The
dial has been calculated for 45°N therefore 45 - 13 means that its plate will be
sloping about 32° to the horizontal. The distance from the pool is about
10m, therefore it needs to be of some size. I am planning on making it
about 2m across.
The main problem seems to be the
choice of materials. I have ruled out wood due to the termites in the
area. I have also ruled out paint as the sun is so very hot most days - except
for the 3 months of rains. It has to be constructed by local labour with
minimal materials available.
I am planning to be there to set
it up and work out the delineation but I want to be sure that we have all the
materials to hand to build it within a few days.
At present my thoughts are to
make it from concrete, preferably off site, so that it can be laid in
position, and dare I say it?, enable me to make small adjustments later if
necessary. This will probably mean that it will have to be made in up to 4
parts plus the gnomon. The ground on site is basically sand. I
originally considered moulding in the hour lines, numerals etc. but think that
this would be too much for the personnel involved. My latest thought is to
make just a flat plate and apply the hour lines as strips - of wood? and house
door type numerals. At least, when the termites eat these strips, they can
easily be replaced!
Therefore I am asking for any
other suggestions that may be more appropriate. I am sure that several
members of this list will have made dials for the tropics and eagerly await
their comments.
Regards,
Mike Cowham. Cambridge, UK. |
- Making a Dial in The Gambia. What materials to use? Mike Cowham