The tables, however, were soon to be turned on her, for Giovanna, who had long despaired of providing an heir to her husband, gave birth a few months later to a male child.  Florence was jubilant, for the Grand Duchess was as beloved as her rival was detested; and the christening of the heir was made the occasion of festivities and rejoicing.  Bianca’s day of triumph seemed at last to be over.  For a time she left Florence to hide her humiliation; but within a year she was back again, to be received with open arms of welcome by the Duke.  During her absence she had made peace with her family, and when her father and brother came to Florence to visit her, they were received by Francesco with regal entertainments, and sent away loaded with presents and honours.

Bianca had now reached the zenith of her power and splendour.  Before she had been back many months the Grand Duchess died, to the undisguised relief of her husband, who hastened from her funeral to the arms of her rival.  Her position was now secure, unassailable; and before Giovanna had been two months in the family vault, Bianca was secretly married to her Grand ducal lover.

Florence was furious.  But what mattered that?  The Venetian Senate had recognised Bianca as a true daughter of the Republic.  She was the legal wife of the ruler of Tuscany.  She was Grand Duchess at last, and she meant all the world to know it.  That she was cordially hated by her husband’s subjects, that the air was full of stories of her extravagance, her intemperance, and her cruelty, gave her no moment’s unhappiness.  For eight years she reigned as Queen, wielding the sceptre her husband’s hands were too weak or indifferent to hold.  Giovanna’s son had followed his mother to the grave; and the child of the slums, who had been so fruitlessly smuggled into her palace, had been legitimated.

The only thorn now left in her bed of roses was the enmity of the Grand Duke’s brother, the Cardinal; and her greatest ambition was to win him to her side.  In the autumn of 1787 he was invited to Florence, and as the culmination of a series of festivities, a grand banquet was given, at which he had the place of honour, at her right hand.  The feast was drawing near to its end.  Bianca, with sparkling eyes and flushed face, looking lovelier than she had ever looked before, was at her happiest, for the Cardinal had at last succumbed to her bright eyes and honeyed words.  It was the crowning moment of her many triumphs, when life left nothing more to desire.

Then it was, at the supreme moment, that tragedy in its most terrible form fell on the scene of festivity and mirth.  While Bianca was smiling her sweetest on the Cardinal she was seized by violent pains, “her mouth foams, her face is distorted by agony; she shrieks aloud that she is dying.  Francesco tries to go to her aid, but his steps are suddenly arrested.  He too is seized by the same terrible anguish.  A few hours later both she and he breathe their last breath.”