The ruler Yüan of Sung once dreamt at midnight that a man with dishevelled hair peeped in on him at a side door and said, 'I was coming from the abyss of commissioned by the Clear Kiang to go to the place of the Earl of the Ho; but the fisherman Yü Zü has caught me.' When the ruler Yüan awoke, he caused a diviner to divine the meaning of the dream, and was told, 'This is a marvellous tortoise.' The ruler asked if among the fishermen there was one called Yü Zü, and being told by his attendants that there was, he gave orders that he should be summoned to court. Accordingly the man next day appeared at court, and the ruler said, 'What have you caught lately in fishing?' The reply was, 'I have caught in my net a white tortoise, sieve-like, and five cubits round.' 'Present the prodigy here,' said the ruler; and, when it came, once and again he wished to kill it, once and again he wished to keep it alive. Doubting in his mind what to do, he had recours...