![Portrait of Leonardo da Vinci attributed to Francesco Melzi](https://cmsadmin.rct.uk/sites/default/files/lead_image_half_height/RC1894_Leonardo%201600%20x%20625_Yellow.jpg)
LEONARDO DA VINCI (VINCI 1452-AMBOISE 1519)
The bones and muscles of a bird's wing
c.1512-13RCIN 912656
Four studies of the bones of a bird's wing, with notes on its construction; a small drawing of a bird flying, with notes on its action; lines bearing proportionate relationships to each other, and fractions expressing those relationships