After this he returned to Argos, and there, at a game of quoits, he had the misfortune to throw the quoit the wrong way, and hit his grandfather, the king, so as to kill him.  Perseus reigned afterwards, and, like all the nobler Greek heroes, kept out the worship of Bacchus and its foul orgies from his dominions; but he afterwards exchanged kingdoms with another king, and built the city of Tiryas.  He lived happily with Andromeda, and had a great many children, whose descendants viewed him as a demi-god, and had shrines to him, where they offered incense and sacrifice; for they thought that he and all the family were commemorated in the stars, and named the groups after them.  You may find them all in the North.  Andromeda is a great square, as if large stars marked the rivets of her chains on the rock; Perseus, a long curved cluster of bright stars, as if climbing up to deliver her; her mother Cassiopeia like a bright W, in which the Greeks traced a chair, where she sat with her back to the rest to punish her for her boast.  Cepheus is there too, but he is smaller, and less easy to find.  They are all in the North, round the Great Bear, who was said by the Greeks to be a poor lady whom Juno had turned into a bear, and who was almost killed unknowingly by her own son when out hunting.  He is the Little Bear, with the pole star in his tail, and she is the Great Bear, always circling round him, and, as the Greeks used to say, never dipping her muzzle into the ocean, because she is so far north that she never sets.