Diagnosis Impossible — Edward D. Hoch

This collection is set in New England during the 1920's and the 1930's, and features country doctor Sam Hawthorne who specializes in locked room and other impossible crimes. Among the 12 stories is the classic tale of a horse and buggy that enter a covered bridge -- and vanish. Introduction by the author; Sam Hawthorne chronology and bibliography by Marvin Lachman.