So, this is where we encountered the first real set-back. But let's see what I planned to do:

This wobbly thing is what I thought would suffice to create the clay/loam dome.

We prepared everything and put the mould in place:

The chamotte bricks are not yet pit in place in the above picture. It was just to test the fit. So, we made a huge batch of mud/sand/straw and began building the dome:

What happened was the following:

The mould gave way because it was much too soft and wobbly. We added pieces of wood to no avail...

Second mistake was the clay. It was much too rich and gave way under its own weight. We gave up after an hour or so because there was no improvement to our situation.

I had to rethink the mould...