Another problem of The chess mysteries of Sherlock Holmes by
I'll shorten the story.
Sherlock Holmes enters a room and sees a chess-set with a shilling
on h4, representing a missing piece. He is then challenged to deduce
what the missing piece is. Of course he succedes.
White: Kh8, Rd7, Rd8, a5, b4, c3, d3, e2, g3, h2
Black: Kb7, Na1, Nc8, a6, a7, c4, c5, d6, e7, g7
h4: a shilling, representing the missing piece
Who can tell me what the missing piece is?