Muscles of the Torso, Side View - by Leonardo da Vinci
Again, this view of the muscles of the torso seen from the side is obviously informed by dissection, even though these are superficial muscles which show clearly under the surface of the skin. In the lower sketch Leonardo shows some of the deeper layer of muscles as they work under the superficial ones.
His handling of the tonal values in the drawings makes the most of the roundness of the muscles and gives a clear picture of the way the musculature lies across the ribcage and around the gut. His notes give an indication of how the muscles attach to the skeleton and to one another.