Secondly, line can function to define interior details. In Michelangelo’s drawing titled Head of a Satyr, lines are placed within the hair, on the surface of the cheek, the forehead, and downward along the neck.




These lines can be densely packed or widely spaced and are called hatching. They can be parallel in direction or overlap in a cross-hatching pattern. The denser the packing, the darker the area of the image. This darker area is visually read as a shadow, as opposed to areas void of hatching or blank areas which are read as lighter. Again, visually we read shadows as farther away from us, as if in a valley or dip in the surface, and lighter areas are read as the hills, or higher points of elevation. We will refer to the resulting bumpiness of surface highs and lows as hills and valleys as they help us read the surface as three-dimensional. Whereas Clemente’s women are perceived as flat cutouts, Michelangelo’s face is three-dimensional with much variation in the surface - more life-like and more reflective of disegno esterno.