 While he speaks, Borella rushes in to tell of a fresh troop of soldiers, marching against the people with Alfonso at their head.Knowing that Masaniello alone can save them, the fishermen entreat him to take the command of them once more and Masaniello, though deadly ill and half bereft of his reason, complies with their request.The combat takes place, while an eruption of Vesuvius is going on.