One of the many war machines created by Leonardo da Vinci was the giant crossbow. This huge weapon was designed to be very intimidating to the enemies. Typical crossbows that shoot arrows were a common war tool, but this giant version was meant to project much more destructive things such as boulders or bombs. The sketch of this invention was designed to be over 20 meters wide, sit on 6 wheels, and be made out of a flexible wood. The projectile could either be set off by soldiers pulling on the trigger or hammering it. Leonardo believed the enemies would be more intimidated and fearful of the size of the machine than the posssible physical damage. Image source: Wikimedia Commons, Giant Crossbow, image listed as public domain in the United States, it is a photographic reproduction of a public domain work of art.