What weapon did Leonardo da Vinci design with a bow far larger than a normal crossbow?

Leonardo da Vinci designed a giant crossbow, also called a giant crossbow or giant cross-bow, as a siege weapon.

The drawing appears in the Codex Atlanticus and shows an enormous bow mounted on a wheeled frame. Leonardo’s intention was to make the weapon imposing and able to launch large stones or bolts. A complex system of gears and a winding mechanism would have helped bend the bow, since a person could not draw it directly.

The design was probably never built and used in battle. Renaissance military engineers often presented spectacular machines to patrons, and the giant crossbow combines practical mechanics with visual intimidation. Its large dimensions made transport, construction, and safe operation difficult.

It should not be confused with Leonardo’s multi-barrel gun, another military design. The crossbow used stored elastic energy in a bent bow; the gun concept relied on gunpowder and multiple barrels.