Which colour strikes most? An object at a distance is most
conspicuous, when it is lightest, and the darkest is least visible.
An exceptional case.
292.
Of the edges [outlines] of shadows. Some have misty and ill defined
edges, others distinct ones.
No opaque body can be devoid of light and shade, except it is in a
mist, on ground covered with snow, or when snow is falling on the
open country which has no light on it and is surrounded with
darkness.
And this occurs [only] in spherical bodies, because in other bodies
which have limbs and parts, those sides of limbs which face each
other reflect on each other the accidental [hue and tone] of their
surface.
An experiment.
293.