Hephaistos splits open the skull of Zeus with a mallet, releasing the goddess Athene from his head. The king of the gods is shown seated on a swan-backed chair, holding a lightning bolt in his hand. A miniature Athene springs from his head, already equipped with a shield. Hephaistos waves one hand, in imitation of an Eileithyia (birth goddess) bringing forth a child. In the other hand he holds a two-headed mallet or axe.
“Now Zeus, king of the gods, made Metis (Wise Counsel) his wife first, and she was wisest among gods and mortal men. But when she was about to bring forth the goddess bright-eyed Athene, Zeus craftily deceived her with cunning words and put her in his own belly, as Gaia (Earth) and starry Ouranos (Heaven) advised. For they advised him so, to the end that no other should hold royal sway over the eternal gods in place of Zeus; for very wise children were destined to be born of her, first the maiden bright-eyed Tritogeneia, equal to her father in strength and in wise understanding; but afterwards she was to bear a son of overbearing spirit, king of gods and men. But Zeus put her into his own belly first, that the goddess might devise for him both good and evil.”