Rodomont, when he had got rid of the hermit, again applied to the sad lady, heartless with affright, and, in the language used by lovers, said, “she was his very heart, his life, his light.”  Having laid aside all violence, he humbly sued that she would accompany him to his retreat, near by.  It was a ruined chapel from which the monks had been driven by the disorders of the time, and which Rodomont had taken possession of.  Isabella, who had no choice but to obey, followed him, meditating as she went what resource she could find to escape out of his power, and keep her vow to her dead husband, to be faithful to his memory as long as life should last.  At length she said, “If, my lord, you will let me go and fulfil my vow, and my intention, as I have already declared it, I will bestow upon you what will be to you of more value than a hundred women’s hearts.  I know an herb, and I have seen it on our way, which, rightly prepared, affords a juice of such power, that the flesh, if laved with it, becomes impenetrable to sword or fire.  This liquor I can make, and will, to-day, if you will accept my offer; and when you have seen its virtue you will value it more than if all Europe were made your own.”

Rodomont, at hearing this, readily promised all that was asked, so eager was he to learn a secret that would make him as Achilles was of yore.  Isabella, having collected such herbs as she thought proper, and boiled them, with certain mysterious signs and words, at length declared her labor done, and, as a test, offered to try its virtue on herself.  She bathed her neck and bosom with the liquor, and then called on Rodomont to smite with all his force, and see whether his sword had power to harm.  The pagan, who during the preparations had taken frequent draughts of wine, and scarce knew what he did, drew his sword at the word, and struck across her neck with all his might, and the fair head leapt sundered from the snowy neck and breast.

Rude and unfeeling as he was, the pagan knight lamented bitterly this sad result.  To honor her memory he resolved to do a work as unparalleled as her devotion.  From all parts round he caused laborers to be brought, and had a tower built to enclose the chapel, within which the remains of Zerbino and Isabella were entombed.  Across the stream which flowed near by he built a bridge, scarce two yards wide, and added neither parapet nor rail.  On the top of the tower a sentry was placed, who, when any traveller approached the bridge, gave notice to his master.  Rodomont thereupon sallied out, and defied the approaching knight to fight him upon the bridge, where any chance step a little aside would plunge the rider headlong in the stream.  This bridge he vowed to keep until a thousand suits of armor should be won from conquered knights, wherewith to build a trophy to his victim and her lord.