She was now in the very prime of her beauty, and a Queen in all but the name.  Between her and her full Queendom were but two obstacles—­her lover’s plain, unattractive wife, and her own worthless husband; and of these obstacles one was soon to be removed from her path.

Pietro, who had been made chamberlain to the Tuscan Court, was more than content that his wife should go her own way, so long as he was allowed to go his.  He was kept very agreeably occupied with love affairs of his own.  The richest widow in Florence, Cassandra Borgianni, was eager to lavish her smiles and favours on him; and the knowledge that two of his predecessors in her affection had fallen under the assassin’s knife only lent zest to a love adventure which was after his heart.  Warnings of the fate that might await him in turn fell on deaf ears.  When his wife ventured to point out the danger he retorted, “If you say another word I will cut your throat.”  The following night as he was returning from a visit to the widow, a dagger was sheathed in his heart, and Pietro’s amorous race was run.

Such was the end of the bank-clerk and his eleventh-hour glories and love adventures.  Now only Giovanna remained to block the way to the pinnacle of Bianca’s ambition; and her health was so frail that the waiting might not be long.  Giovanna had provided no successor to her husband (who had now succeeded to his Grand Dukedom); if Bianca could succeed where the Grand Duchess had failed, she could at least ensure that a son of hers would one day rule over Tuscany.

Thus one August day in 1576 the news flashed round Florence that a male child had been born in the palace on the Via Maggiore.  Francesco was in the “seventh heaven” of delight.  Here at last was the long-looked-for inheritor of his honours—­the son who was to perpetuate the glories of the Medici and to thwart his brother, the Cardinal, who had so confidently counted on the succession for himself.  And Madame Bianca professed herself equally delighted, although her pleasure was qualified by fear.

She had played her part with consummate cleverness; but there were two women who knew the true story of the birth of the child, which had been smuggled into the palace from a Florence slum.  One was the changeling’s mother, a woman of the people, whom a substantial bribe had induced to part with her new-born infant; the other was Bianca’s waiting woman.  These witnesses to the imposture must be silenced effectually.

Hired assassins made short work of the mother.  The waiting-maid was “left for dead” in a mountain-pass, to which she had been lured; but she survived long enough at least to communicate her secret to the Grand Duke’s brother, the Cardinal Ferdinand de Medici.

Bianca was now in a parlous plight.  At any moment her enemy, the Cardinal, might betray her to her lover, and bring the carefully planned edifice of her fortunes tumbling about her ears.  But she proved equal even to this emergency.  Taking her courage in both hands, she herself confessed the fraud to the Grand Duke, who not only forgave her (so completely was he under the spell of her beauty) but insisted on calling the gutter-child his son.