MAILE MELOY SAYS IT'S FOR AGES ten and up, and I think that includes 52. This delightful secret garden of a novel contains all of your favorite things. It's as if Meloy put London, L.A., potions, mysterious old shops, great books, adventure, and the glimmer of young love in a jar and shook it up. One spoonful and you're in. Janie Scott, the novel's heroine, is a combination of Scout (from To Kill a Mockingbird) and Lucy (from the Chronicles of Narnia). She is spunky and imaginative and wise beyond her years. She teams up with Benjamin Burrows (the apothecary's son) to protect the book that holds the cure for everything, including homesickness. What a romp! What a lark!