Leonardo da Vinci designed a mechanical drum that could produce a repeating musical rhythm.
The instrument used a rotating cylinder or drum fitted with pegs. As the drum turned, the pegs operated levers connected to hammers, which struck a drum surface. Changing the peg arrangement could alter the rhythm. The concept belongs to Leonardo’s broader interest in automata and programmable mechanical motion.
The device was not an electronic instrument and did not rely on recorded sound. Its musical pattern was encoded physically in the placement of pegs, a principle later seen in mechanical music boxes and other pinned-cylinder instruments.
Some accounts connect the drum with Leonardo’s mechanical lion or other court entertainment projects, but the surviving drawings and later reconstructions are the safest basis for describing its mechanism. The design is distinct from the viola organista, which used a keyboard and continuously bowed strings rather than percussion hammers.