Wont take long to complete the fourth wall (3 blocks!), but we want to get it lined and levelled up with the far corner, and begin the back wall before placing the third block. The side wall nearest the camera will have a gap at the end of it which will ultimately be for our drainpipe to pass through, but during construction will also serve as quite a useful little gap to push the wheelbarrow through when stripping the topsoil from inside the building.
We were prevented from doing any more last night when the cement mixer broke. After completing the first two steps that anyone would take after something breaks (an initial period of standing and looking at it in a confused manner to see if that would make it work again, and a secondary period of randomly hitting it with a hammer to see if that would make it work again), I eventually started looking for what might be wrong, and found the drive belt slipping. We should just be able to tighten this up and start again tomorrow.