A Treatise on Painting
by Leonardo da Vinci, translated by John Francis Rigaud
Of the blueish Appearance of remote Objects in a Landscape
4015747A Treatise on Painting — Of the blueish Appearance of remote Objects in a LandscapeJohn Francis RigaudLeonardo da Vinci

Chap. CCXC.Of the blueish Appearance of remote Objects in a Landscape.

Whatever be the colour of distant objects, the darkest, whether natural or accidental, will appear the most tinged with azure. By the natural darkness is meant the proper colour of the object; the accidental one is produced by the shadow of some other body.