R.J. Hollingdale, Nietzsche: The Man and His Philosophy
(London: Routledge & Kegan Paul, 1965), p. 59:
He suggested the students might like to read the description of the Shield of Achilles in the Iliad during the summer vacation: at the beginning of the following semester he asked one of them if he had in fact read it. The student (his name has not been recorded) said he had, although this wasn't true. 'Good, then describe the shield of Achilles for us,' said Nietzsche. An embarrassed silence followed, which he allowed to continue for ten minutes -- the time he thought a description of Achilles' shield should have taken -- pacing up and down and appearing to be listening attentively. Then he said: 'Very well, X has described Achilles' shield for us, let us get on.'