The Adventures of Jimmie Dale

Frank L. Packard was a Canadian novelist. He was born in Montreal, Quebec and as a young man went to work as a civil engineer for the Canadian Pacific Railway. His experiences working on the railroad led to his writing a series of mystery novels, the most famous of which featured a character called "Jimmie Dale"; who first appeared in the novel The Adventures of Jimmie Dale. He was a wealthy playboy by day, but at night put on a costume and became The Grey Seal, who enters businesses or homes and cracks safes, always leaving a grey seal behind to mark his conquest, but never taking anything. Jimmie Dale/The Gray Seal is often credited with popularizing and evolving what would greatly influence later pulp and comic book heroes. He also established the concept of a hero's secret hideout or lair, The Sanctuary, a precursor of the Batcave or the Fortress of Solitude.