Look for "Leaf 27 Service To Humanity" in Ellery Queen(Frederic Dannay and Manfred B. Lee), In the Queen's Parlor and Other Leaves From the Editor's Notebook. This brief essay which originally appeared in Ellery Queen's Mystery Magazine is a perceptive appreciation of Earl Der Biggers and his most famous creation. The book is filled with Dannay and Lee's reminiscences about the great writers of the Golden Age of the mystery story and is well worth tracking down for anyone who wants a behind the scenes look at the greats of that era and their achievements in the mystery field.