Pennant Hullcracker

A hullcracker was an invention by Odiss Pennant I. It was designed to be an anti-pirate measure along the Emerald River, and were first implemented in Kodonholm.

Design

A Pennant hullcracker was originally little more than a toothed, underwater awl, pointed at a 45-degree angle inverse to the surface of a river. If a ship, even one relatively draft-shallow, attempted to cross over, it would become entangled on the teeth or strike the hard center peg. Center pegs were typically made of adamantine. The damage to a ship's keel was often catastrophic, especially when hullcrackers were deployed in large numbers. Even a single hullcracker could slow a ship significantly, allowing defenses to be mustered or other measures to be taken against the offending vessel.

Only small rowboats and barges could pass over an underwater hullcracker. Later versions of a hullcracker involved steam pistons or clockworks, allowing them to be retracted to allow waterborne traffic. These piston-powered hullcrackers could also be used to chew through a ship's keel by repeatedly deploying the mechanisms.