OF PAINTING.
Of various colours which are none of them blue that which at a great distance will look bluest is the nearest to black; and so, conversely, the colour which is least like black will at a great distance best preserve its own colour.
Hence the green of fields will assume a bluer hue than yellow or white will, and conversely yellow or white will change less than green, and red still less.
Taken from The Notebooks of Leonardo da Vinci edited by Jean Paul Richter, 1880.