A Treatise on Painting, by Leonardo da Vinci
Senex and Taylor, London
In an Autumn-Piece, let every thing be represented suitably to the Season. Thus towards the beginning of that Quarter, let the Leaves, found on the oldest Branches of Trees, begin to appear pale, and in a greater or less Degree, as the Soil is more barren or fertile; still avoiding the common Fault of Painters, who make no scruple of giving the same Colour, and the same kind of Verdure to all sorts of Trees, provided they be but view'd from equal distances. The same thing must be understood of Meadows, Rocks, Trunks of Trees, and of all kinds of Vegetables; wherein you must always introduce a variety, in imitation of Nature, who in this, as in other parts of her Kingdom, diversifies her Works, in a manner that surpasses all imagination.