This final project for my book "Stacking the Deck" combined the more difficult techniques taught in the book to form a very delicate structure. The first one built was much shorter, as time went on, I got more confident and kept pushing them taller. This design shows the possibilities of getting more comfortable with the corbeling technique and a curving roofline. It really only takes a small touch to knock one of these structures over. At an event when I made one of these buildings, a young boy said, "Mom, look, it's an oil derrick." I hadn't thought of that before, but I suppose it's as good a name for it as any.