When we think of scary, we ordinarily think of the sights–dark hallways and spider webs, bloody masks and crumbling gravestones, and to a lesser extent, sounds–creaking doors and spooky voices–cue Vincent Price’s Witchcraft Magic!–but what about creepy smells? So many write about the nostalgic scents, the comforting ones of kitchens and gardens, lime-flower tea and madeleines, but what about those creepy smells we prefer to avoid or forget–those of blood and the grave, caves and decay? What makes them provoke …