Sammy was having a tough time making any headway with the concrete smashing yesterday, so I had a whack at it for a few minutes when I first went down to the shop today to get myself warmed up a bit. I got out the 22mm Stone drill and a wedge and feather set. A couple of holes and I had one of the corners and one side off in a big slab. In case you have never used these primitive exploiters of the inclined plane principle, the wedge is of course self explanatory. A wedge shaped piece of hardened steel. The feathers sound a little less plausible, but they are two wedges themselves with one side rounded to the same diameter as the hole. You pop the feathers in the hole and then drive the wedge between them. The fat end of the feathers goes into the hole first and the inside surfaces are flat allowing the wedge held between them to bear very efficiently on the inner surface of the hole and split just about anything with enough holes and wedges. I hope Sammy will enjoy having a go at that tomorrow. A happy leap day to all.