The Adventure of Black Peter (Unabridged‪)‬

Dr. Watson's account of the strange death of Captain Peter Carey begins one morning with Holmes returning to Baker Street with a "huge barbed-headed spear tucked like an umbrella under his arm." The instrument, the facts unfold, duplicates the weapon which has been driven so violently through the victim's body that it has been discovered pinned to the wall like an insect.