renaissanceera masterpieces fantastical machines anatomical studies and geometric s on yellowed parchment

drawings illustrations anatomical studies inventions designs concepts drafts renderings blueprints plans sketches compositions artwork innovative masterpieces craftsmanship mechanical engineering machinery robotics automatons flying machines ornithopter helical proportions geometry perspective sfumato chiaroscuro shading sketchbook journals notebooks parchment paper pencils charcoal vintage historical artistry geometric patterns fantastical renaissance art technical artistic early details handdrawn