🔫 Von Herder's Air-Gun
A silent, powerful air-rifle firing soft revolver bullets, built by a blind German mechanic to Moriarty's order for one marksman's use. It killed Ronald Adair through a closed window and dented a wax Holmes an inch from history.
A silent gun built for one marksman
The air-gun is a marvel of murderous engineering: silent, powerful, and firing soft, expanding revolver bullets — built by the blind German mechanic Von Herder to Moriarty's own order, for the exclusive use of the one man capable of using it, Colonel Sebastian Moran. A rifle that makes no sound and leaves a revolver's wound was, for its time, an almost supernatural instrument.
The weapon that closes the Hiatus
Moran uses it to kill the Honourable Ronald Adair through a closed window across a street — an impossible crime until Holmes deduces the impossible weapon. Then Holmes turns it on its owner: a wax bust in the Baker Street window draws Moran to the empty house opposite, where the air-gun's dent in the dummy's head is the evidence that ends the last of Moriarty's men.