 When the Duke of Albemarle was informed, he agreed to detach a squadron of 20 generally fast or well-armed ships under Prince Rupert to block the Strait of Dover, provided he were left with at least 70 ships to fight the Dutch.Rupert was detached on 29 May (Julian calendar) to prevent Beaufort passing through the English Channel to join the Dutch fleet.In the event the French fleet did not appear, because Beaufort, who had left Toulon in April 1666 with 32 fighting ships, delayed at Lisbon for six weeks, during which time the English and Dutch fleets fought the Four Days' Battle, one of the longest naval engagements in history.