This Atlas was a great king, and his kingdom stretched westward till it touched the ocean which surrounds the earth. And that is why this part of the sea is called the Ocean of Atlas, or Atlantic Ocean. The name of his kingdom was Mauritania, now called Morocco, where he owned a thousand flocks, and orchards with apples of gold. And he had seven beautiful daughters, whose names were Alcyone, Asterope, Celæno, Electra, Maia, Merope, and Taygeta. Six of these married gods; Merope alone married a mortal. After their death they were honored by being set as stars in the sky, where you may often see the seven sisters clustered together in a beautiful constellation called the Pleiades. But it is very difficult to see Merope, because she married a mortal instead of a god, and therefore shines dimly. If you can see more than six of the seven sisters you have good eyes. Of all the Pleiades Maia is the brightest, for she was chosen by Jupiter. She had a son named Mercury, and a promising child he must have been. For on the very day he was born he stole the oxen of King Admetus of Thessaly, although (as you may remember) Apollo himself was then the king's herdsman. And Mercury not only stole the oxen, but ran away with Apollo's quiver of arrows. Proud of this feat, he stole the zone of Venus, the sword of Mars, and the hammer of Vulcan; and at last he carried off the very scepter of Jupiter. Instead of punishing him, however, Jupiter was so delighted with his cleverness and impudence that he made Mercury his chief messenger and cup-bearer. He also gave him a winged cap, wings for his heels, a short sword, and a scepter called _caduceus_--a rod round which two living serpents coiled. The winged cap was called _petasus_, and whenever he put it on he became invisible; the wings for his heels were called _talaria_, and made him able to fly faster than lightning to any place he pleased. The _caduceus_ was a magic wand. It first belonged to Apollo, who used to drive the flocks of King Admetus with it. But when Mercury invented the lyre, he gave the lyre to Apollo in exchange for the _caduceus_. The lyre became Apollo's favorite instrument, and Mercury used the _caduceus_ to drive the flocks of dead souls to Hades, for that was one of his duties. He could also send people to sleep with it, and could bring back the dead to life by touching them with its point. You will always know a picture or statue of Mercury from his _caduceus_, and from the wings on his cap and heels.