Note 49 — Chapter III
Reading edition
Mr. Vertue the engraver made a very ingenious conjecture on this story; he supposes that Apelles did not draw a straight line, but the outline of a human figure, which not being correct, Protogenes drew a more correct figure within his; but that still not being perfect, Apelles drew a smaller and exactly proportioned one within both the former.—Walpole's note.