The Parrot's Beak — Roy Vickers

There are many Scotland Yards in fiction. But one that stands out in the mind of aficionados is the unique creation of Roy Vickers in the Department of Dead Ends. This special department of the Yard collects and stores the detritus of unsolved crimes until some future time when the material may be utilized or discarded ... The informative introduction collects the few known facts about Vickers's life, and assesses his work and place in the history of detective fiction.