The Eye Seeing Through a Window; Dark Objects on a Light Field
A lettered diagram of vision through an aperture, with a note that a dark object looks slimmer against a bright field
At the top of the sheet a lettered diagram shows the eye viewing through a window (finestra), with rays drawn to the points a b, c, p, n m and f d e. A short caption beneath begins to state that the eye which does not see an object too distant..., breaking off, while a further note explains that a dark object seen against a luminous field appears of smaller thickness than it would against a field darker than itself.
On this page
Lettered diagram of the eye and window (finestra)
A construction at the upper right shows the eye directing rays through a window (finestra) toward the labelled points a b, c, p, n m, f d e.
Caption on seeing a not-too-distant object
A brief caption below the figure begins 'The eye that does not see an object too [distant]...' and breaks off incomplete.
A dark object looks slimmer against a bright field
A dark object seen against a luminous field will appear of smaller thickness than if it were set against a field darker than itself.