HOW WHITE BODIES SHOULD BE REPRESENTED.

If you are representing a white body let it be surrounded by ample
space, because as white has no colour of its own, it is tinged and
altered in some degree by the colour of the objects surrounding it.
If you see a woman dressed in white in the midst of a landscape,
that side which is towards the sun is bright in colour, so much so
that in some portions it will dazzle the eyes like the sun itself;
and the side which is towards the atmosphere,--luminous through
being interwoven with the sun's rays and penetrated by them--since
the atmosphere itself is blue, that side of the woman's figure will
appear steeped in blue. If the surface of the ground about her be
meadows and if she be standing between a field lighted up by the sun
and the sun itself, you will see every portion of those folds which
are towards the meadow tinged by the reflected rays with the colour
of that meadow. Thus the white is transmuted into the colours of the
luminous and of the non-luminous objects near it.

The methods of aerial (567--570).