"Up there, look," said Hermione. She pointed to a strange, pointy object on top of a war memorial at the far end of the square. It was rotating on its axis. "Scanning Stave. They were only just installing it when we moved away. They are everywhere now. It sweeps a constant spell around the tracking zone, but if we time it right we should be able to stay in the blind spot. When I tell you, just run! Wait ... wait for it ... now!"