Posts #9 & #10 describe different ways of using bricks, building down from the top.
I suspect the bricks have to be wedge shaped, you could push a rectangular brick out of the wall without disturbing the bricks round it.
sounds all too compicated for me, l like the idea of drilling a smallish bore 4 or 5" maybe, l see some people hammer a steel tube into the ground pull it back out remove the earth from the inside and repeat
theres a vid on here of this process
http://www.consallen.com/
at least this way you could do it yourself ??
l have a load of these galv steel tubes about 5" in diameter h'mmm

Robin would have to find a new home though
