HOW YOU SHOULD SET TO WORK TO DRAW A HEAD OF WHICH ALL THE PARTS
SHALL AGREE WITH THE POSITION GIVEN TO IT.

To draw a head in which the features shall agree with the turn and
bend of the head, pursue this method. You know that the eyes,
eyebrows, nostrils, corners of the mouth, and sides of the chin, the
jaws, cheeks, ears and all the parts of a face are squarely and
straightly set upon the face.

[Footnote: Compare the drawings and the text belonging to them on
Pl. IX. (No. 315), Pl. X (No. 316), Pl. XL (No. 318) and Pl. XII.
(No. 319).]

Therefore when you have sketched the face draw lines passing from
one corner of the eye to the other; and so for the placing of each
feature; and after having drawn the ends of the lines beyond the two
sides of the face, look if the spaces inside the same parallel lines
on the right and on the left are equal [12]. But be sure to remember
to make these lines tend to the point of sight.

[Footnote: See Pl. XXXI, No. 4, the slight sketch on the left hand
side. The text of this passage is written by the side of it. In this
sketch the lines seem intentionally incorrect and converging to the
right (compare I. 12) instead of parallel. Compare too with this
text the drawing in red chalk from Windsor Castle which is
reproduced on Pl. XL, No. 2.]

Of the light on the face (574-576).