Leonardo da Vinci designed the viola organista, a keyboard instrument using rotating bows instead of plucked strings.
The instrument combined a keyboard with strings and a continuously moving bow mechanism. Pressing keys selected strings, while rotating wheels or bows produced sustained tones. Leonardo’s concept aimed to give a keyboard player an expressive bowed-string sound without requiring the player to hold and move a conventional bow.
The viola organista was never completed by Leonardo as a standard working instrument. Several modern builders have created reconstructions based on his drawings, and these instruments demonstrate the basic principle while differing in construction and interpretation.
The device is often confused with Leonardo’s barrel-organ designs. A barrel organ automates musical actions through a pinned cylinder, whereas the viola organista is played from a keyboard. Its name reflects the combination of bowed-string sound and organ-like keyboard control.