New Looks For Old Books
First: Disappearing Fore Edge is the art of painting something on the edge of book pages that can only be seen when they're fanned. "Supposedly, Charles II of England had a lady friend, a duchess, ( I'm guessing Barbara Castlemaine, first Duchess of Cleveland ) who often borrowed his books, sometimes forgetting to return them. So, the king commissioned the court painter, Sir Peter Lely, and the court bookbinder, Samuel Mearne, to devise a secret method by which his books could be identified. Between the two, they worked out the clever technique. Some weeks later, when the king was visiting the duchess, he spotted a familiar looking book on a shelf. Taking it down he said, “I’ll just take my book along with me.” “But sire,” the lady protested, “that book is mine.” “Oh?" The king raised his brows. Then, with a sly smile, he fanned out the pages and revealed what had been painted on them--the royal coat of arms. The gilding on the outer edges had completely hidden the identification. Acknowledging that Charles had outwitted her, the duchess sank in a deep curtsy before her king.
"The majority of extant examples of fore-edge painting date to the late 19th and early 20th centuries." Probably, now, it's a lost or barely-surviving art but I wrote a short story where Disappearing Fore Edge helped the sleuth solved the crime. It's somewhere on a thumb drive.