What military machine did Leonardo da Vinci propose for launching several stones at once with a large tensioned frame?

Leonardo da Vinci proposed a multiple sling catapult, a military machine designed to launch several stones at once from a large tensioned frame.

Leonardo’s military notebooks contain many studies of projectile weapons, including devices that used stored tension, rotating arms, and multiple throwing elements. The multiple sling catapult was intended to increase the number of projectiles released during an attack, potentially producing a broad strike against an opposing formation or defensive position.

The design belongs to a long history of torsion and tension weapons. It was not a conventional trebuchet, which uses a counterweighted throwing arm, and it was not a giant crossbow, which launches a single bolt with a bowstring. Its defining feature was the use of several slings or throwing elements mounted within one large machine.

As with many of Leonardo’s military sketches, the surviving drawing documents an idea rather than a proven battlefield device. His proposals frequently emphasized dramatic scale and mechanical ingenuity, and some would have been difficult to construct, aim, or reload in practice.