Boy Engineer and Long-Trousers seem pleased to be doing something practical. They’ve carried the metal frames that arrived this morning into the garage and have used them to build something. They back up to contemplate their work, then Boy Engineer moves in again and pounds with a hammer. He moves in a circle, following something that turns as he beats it, while Long-Trousers and a trusted orange-vest observe.

Finally, with a virtual back pat, all three swagger jauntily round a wall of bricks and vanish into the ruins.