Far out in the west, near the ocean flowing round the world, were herds of purple oxen, guarded by a two-headed dog, and belonging to a giant with three bodies called Geryon, who lived in the isle of Erythria, in the outmost ocean.  Passing Lybia, Hercules came to the end of the Mediterranean Sea, Neptune’s domain, and there set up two pillars—namely, Mounts Calpe and Abyla—on each side a the Straits of Gibraltar.  The rays of the sun scorched him, and in wrath he shot at it with his arrows, when Helios, instead of being angry, admired his boldness, and gave him his golden cup, wherewith to cross the outer ocean, which he did safely, although old Oceanus, who was king there, put up his hoary head, and tried to frighten him by shaking the bowl.  It was large enough to hold all the herd of oxen, when Hercules had killed dog, herdsman, and giant, and he returned it safely to Helios when he had crossed the ocean.  The oxen were sacrificed to Juno, Eurystheus’ friend.