About ten years ago I bought a ratty coverless Adventure Comics #37 from April 1939 for about $50. Why? The selling point was an internal text ad at the top of one of the pages promoting some new character called The Batman. The ad reads: "The Batman! This new thrilling adventure strip starts in the May issue of Detective Comics! Don't miss it!" It's kind of neat to have a teeny-tiny slice of Batman's early history. Can anyone confirm this ad is real? Are there any other Golden Age promotions for iconic characters that actually came out before the character's first appearance?