When the Argo approached the Symplegades,--or Clashing Islands,--Jason remembered the words of Phineus, who had advised him to let free a dove, whose speed was less than that of his swift vessel, before he attempted a passage. If it flew easily between the rocks, then the ship could safely follow it with no chance of being ground to pieces as the islands clashed together. When the Argonauts reached this dangerous spot, Jason sent a dove out before him. He watched its flight anxiously, and when it glided between the rocks with only a tail feather caught, he guided the ship so close behind it that, as he slid through the opening made by the rebound of the islands, the deadly rocks merely grazed his rudder. Since their destructive power depended on allowing no vessel to pass them unharmed, the evil force that the islands possessed was now broken, and they were henceforth chained fast to the bottom of the sea. At last the Argo reached the shores of Colchis, and Jason made known to King Æetes his desire to possess the golden fleece. The owner of that wonderful pelt was very naturally not ready to give it to even the boldest stranger; but he treated the Argonauts kindly, and even promised to bestow upon Jason the coveted fleece if he could catch and harness to a plow two brazen-hoofed, fire-breathing bulls. Then, having done this, he must plow up a certain piece of ground sacred to Mars, and sow the field with dragon's teeth just as Cadmus had done.[95] Last of all he must conquer the armed giants that would spring up in the field after the sowing, and then slay the dragon that guarded the golden fleece. This was certainly enough to daunt any hero, but Jason, relying on the help of Juno, agreed to the king's terms and went down to the seashore, where his ship lay, to consult the figurehead who had never yet failed him. On the way he met Medea, the king's daughter, who was much taken with the young stranger's beauty, and hoped to induce him to marry her. Medea herself was very beautiful, and being also a sorceress she was an invaluable ally in the adventure that had brought Jason and his friends from a far-distant land. So before many days had passed Medea plighted her troth to the young hero who needed help sorely and the king's daughter promised to give him the aid of her magic arts.