Viola organista

The Viola organista is a musical instrument designed by Leonardo da Vinci. It consists of a row of keys which, when struck, pushes a string against a moving bow.

History
Leo invented the Viola organista in time for carnival. When Lorenzo de' Medici saw it, he was impressed and asked Leo to accompany his singing for the masked ball at the Medici Palace. Later, Lisa Gherardini was extremely smitten as she watched Leonardo perform. (The Betrothal Ball)