Leonardo noticed that anything fired (cannons, cross bows and the like) was notoriously inaccurate and ineffective. He thought that by designing a bullet which could fly straighter and faster, he would greatly help improve the effectiveness of a range of firing devices. By looking more closely at bullets and arrows, he studied how air and water currents influence the way these objects move. He designed a new type of bullet, with a long pointed shape and directional wings to increase its aerodynamic efficiency, allowing projectiles to fly straight and true.