Before the earth former for the dome can be built a
support of timber is needed at the level of the wall.
This gives a firm platform for building the earth form.
The platform should be made of several small pieces
so it will collapse easier.
The timber platform is supported by bricks and timber
from underneath. When the dome has finally been cast
and set hard, these supports can pushed out and the
earth platform will collapse for removal leaving the
dome in place on the kiln walls.