There are on record cases of mules living to the age of eighty, as did one in Athens at the time of the building of the temple; this mule on account of its age was let go free, but continued to assist in dragging burdens, and would go side by side with the other draught beasts and stimulate them to their work; and in consequence a public decree was passed forbidding any corn merchant from driving the creature away from his trays.