Leonardo da Vinci’s viola organista combined a keyboard with bowed strings to imitate the sound of a violin.
Leonardo designed several versions of the instrument during the late 15th century. Pressing keys caused strings to be touched by a continuously rotating wheel or belt, producing sound in a way related to bowed string instruments. The keyboard allowed one player to control the pitches with both hands.
The viola organista was never built during Leonardo’s lifetime, and no single surviving sketch proves that he settled on one final form. Modern makers have constructed working versions from his drawings. It is not a conventional organ because its sound comes from strings rather than pipes, and it is not a normal viola because the performer plays it through a keyboard.