In message <cacouayqkptw49kaqyxexjghpocw_eikv3xei+kctrpqd9le...@mail.gmail.com>
Dan-George Uza <[email protected]> wrote:
> Hello,
>
> Horizontal sundials are often victims of vandalism. I am looking for ideas
> or designs of gnomons which are not that easy to break off i.e. how to
> attach them permanently to the base plate. Can you help?
>
> Thanks,
>
Hi, Dan
If you are interested in 'large-scale' public sundials, which are
virtually vandal-proof - then just create an Analemmatic, using a
person's own shadow to tell the time. It will be interactive, as
well as not needing a gnomon at all - and can be made from a wide
range of materials (stone/concrete/mosaic/wood/metal/etc) to suit
the location. If set into grass, then just 'mow' right over it !
Alternatively, for a 'pedestal-mounted' type dial, then just make
it in the bi-filar form - by using (say) 1cm diameter steel tubes
to create the North/South and East/West horizontal gnomons, whose
shadow intersection shows the time. Any normal vandal would find
it very difficult to bend such tubes. This also has an advantage
of being 'equi-angular', (with 15 degrees between each hour) - so
could be simple to rotate its Hour-ring either for any 'Daylight-
saving' time changes, and/or to accommodate the Equation-of-Time.
Sincerely,
Linda Reid.
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