Shadow's Four Considerations: Quality, Quantity, Site, Figure
The middle tone, the four parts of shadow to weigh in painting, and the aspect of a shadow
The page opens on the middle tone that can be called neither light nor dark but shares equally in both, sometimes halfway between and sometimes nearer one. Leonardo then sets out the four principal things to weigh in the lights and shadows of painting — quality (how dark), quantity (how large relative to neighbours), site (where placed on the limb), and figure (whether triangular, round or square). He adds a fifth, aspect: the direction toward which a shadow's length points, as the shadow of an eyebrow toward the ear or the shadow beneath the eye socket toward the nostril, and holds that aspect should be considered before site. A final chapter begins on the nature of the universal light that encircles and illuminates a shadowy body.
On this page
The middle tone between light and dark
There is a middle that can be named neither light nor dark but shares equally in both; sometimes it stands equally distant from light and dark, and sometimes it is nearer to one than the other.
Quality, quantity, site and figure of shadow
Four principal parts must be considered in painting: quality (which shadow is more or less dark), quantity (its size relative to neighbouring shadows), site (where and on which part of the limb it rests), and figure (whether triangular, round, square, and so on).
The aspect: the direction of a shadow's length
Aspect too must be counted among the shadows: if a shadow has length, one must see toward what it points — the shadow of an eyebrow toward the ear, the lower shadow of the eye socket toward the nostril. Aspect, Leonardo holds, should be set before site.
Universal light encircling a shadowy body
The universal light encircles the part of the shadowy body it sees and illuminates it, varying that illumination with greater or lesser brightness according to how much of that light reaches each part.