The Blue Carbuncle
Two days after Christmas, Watson calls on Sherlock Holmes only to find him scrutinizing an old battered hat. Holmes reveals that Peterson, a commissionaire, saw a man with a goose over his shoulder being assaulted by some ruffians. The man raised his cane to defend himself and broke a window behind him; when he saw Peterson running towards him, he hastily fled, leaving his hat and the goose behind. Peterson sought Holmes for help finding the owner of these treasures, but the only physical clues they discover are a tag on the goose, reading, “For Mrs. Henry Baker” and the initials H.B. inscribed on the inside of the hat.