Overlapping shadows and where colour vanishes in shade
Two bodies' shadows intersect and superimpose from a single light
The folio observes that at long distance the colours of bodies show no difference in their shadowed parts. A first figure, lettered d f, a, m b c n, shows that a single light shining past several bodies can throw mixed derivative shadows that intersect and lie one over the other, with a b c the overlapped region where m c is the shadow of d and b n the shadow of f. A second figure compares a cylindrical and a spherical body to hold that the part of an opaque body brightest under light becomes, once the light is removed, the most deeply shadowed.
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Shadowed colours look alike at a distance
Among the colours of bodies there is no difference, at long distance, in their shadowed parts. Only lit surfaces keep their colours apart over such spans.
Two bodies' shadows intersect and overlap
A single light shining past several bodies can throw mixed derivative shadows that intersect and lie one over another. Here a b c is the overlapped region, since m c is the shadow of d and b n the shadow of f, and the extent of b c a measures how far one shadow covers the other.
The brightest lit part becomes the darkest in shade
That part of an opaque body which is brightest among its illuminated portions will, once the light is removed, remain the most deeply shadowed. A cylindrical and a spherical body are set together to show the varied shadow.