LEONARDO DA VINCI - Studies of the mechanism of breathing
Royal Collection (RLW), 19061v; K/P 154v (detail)
Leonardo made a detailed study of the mechanics of voluntary respiratory movements (yawning and sighing). Here, he focuses on the action of the muscles that raise the ribs. Resorting to his favorite mechanical analogy, he reduces muscular action to the work of a weight lifting a rod via a pulley.