But all Monson’s exploits pale before an action which occurred in Cerimbra roads, in which a great treasure-ship was cut out, in sight of a fortress and eleven galleys, and within hearing of the guns of Lisbon. He was then associated with Admiral Sir Richard Lewson, but the principal part of the service was performed by himself. When the carrack and galleys were discovered lying at anchor, a council was held on board the admiral’s vessel, which occupied the better part of a day, as many of the captains thought it folly to attempt to capture a great ship defended by a fortress and eleven galleys. Monson thought differently, and it was at length agreed that he and the admiral should anchor as near the carrack as they could, while the other and smaller vessels should ply up and down, holding themselves in readiness for any emergency. It is likely, as Southey remarks, that “the sight of these galleys reminded Sir William of the slavery he had endured at Lisbon in similar vessels, if not indeed in some of these identical craft, and he longed to take revenge upon them.” Monson says that in order to show contempt of them, he separated from the rest of the fleet, by way of challenging and defying them. “The Marquis of St. Cruz, General of the Portuguese, and Frederick Spinola, General of the galleys, accepted the invitation, and put out with the intention of fighting him; but they were diverted from their purpose by a renegade Englishman, who knew the force of the vice-admiral’s ship, and that she was commanded by Monson.”