Stone Signal is a magazine story.
Mavis is away at the Works, so Rosie is running her quarry line, taking loads of stone to the beach for wall-building. But on the way, Rosie breaks down in a tunnel. Harold is on patrol looking for her, but he can't find her. Rosie then has an idea, and her crew make the word 'HELP' out of stones. Harold sees it, and has Harvey rescue Rosie.