A painter ought to study universal Nature, and reason much within himself on all he sees, making use of the most excellent parts that compose the species of every object before him. His mind will by this method be like a mirror, reflecting truly every object placed before it, and become, as it were, a second Nature.
Chap. CCCLXI.—Of Statuary.
To execute a figure in marble, you must first make a model of it in clay, or plaster, and when it is finished, place it in a square case, equally capable of receiving the block of marble intended to be shaped like it. Have some peg-like sticks to pass through holes made in the sides, and all round the case; push them in till every one touches the model, marking what remains of the sticks outwards with ink, and making a countermark to every stick and its hole, so that you may at pleasure replace them again. Then having taken out the model, and placed the block of marble in its stead, take so much out of it, till all the pegs go in at the same holes to the marks you had made. To facilitate the work, contrive your frame so that every part of it, separately, or all together, may be lifted up, except the bottom, which must remain under the marble. By this method you may chop it off with great facility[101].
Chap. CCCLXII.—On the Measurement and Division of Statues into Parts.
Divide the head into twelve parts, each part into twelve degrees, each degree into twelve minutes, and these minutes into seconds[102].
Chap. CCCLXIII.—A Precept for the Painter.
The painter who entertains no doubt of his own ability, will attain very little. When the work succeeds beyond the judgment, the artist acquires nothing; but when the judgment is superior to the work, he never ceases improving, if the love of gain do not retard his progress.
Chap. CCCLXIV.—On the Judgment of Painters.
When the work is equal to the knowledge and judgment of the painter, it is a bad sign; and when it surpasses the judgment, it is still worse, as is the case with those who wonder at having succeeded so well. But when the judgment surpasses the work, it is a perfectly good sign; and the young painter who possesses that rare disposition, will, no doubt, arrive at great perfection. He will produce few works, but they will be such as to fix the admiration of every beholder.