Editing Four Days' Battle (section)

===Fourth day, English retreat===
Once the English rear had been subdued, de Ruyter led most of his fleet in pursuit of Albemarle and Rupert, hoping to prevent them joining forces. The English fleet maintained a westward course towards the deep water channel leading to the Thames estuary. Albemarle and Rupert later claimed that their initial aim of their withdrawal was to unite and, if necessary renew the fight the next day, but the poor condition of many ships and their lack of ammunition decided them to continue homeward.<ref>Fox, pp. 268-9</ref> However, other English officers said that the Dutch pursued the retreating English fleet for two hours before deciding to retire back to their own harbours.<ref>Fox, p. 270</ref>

De Ruyter later claimed that he had called off the pursuit of the English fleet because of a thick fog which made navigation difficult, otherwise he would have followed the ships as far as their home ports. The deeply religious De Ruyter interpreted the sudden unseasonal fog bank as a sign from God, writing in his logbook "that He merely wanted the enemy humbled for his pride but preserved from utter destruction". However, the fog was only temporary and de Ruyter had only around 40 ships under his immediate command, with others disabled and returning to the Netherlands or dealing with prizes, and Albemarle had almost as many, including several large vessels, which posed a significant risk to the exhausted Dutch fleet.<ref>Fox, p. 270</ref>

By the end of the third day de Ruyter had already secured strategic victory, as the loss of ships and damage to the remainder would have prevented the English fleet interfering with the Dutch East Indies trade or preventing a French fleet joining the Dutch. Even had he retreated on the fourth afternoon, as Albemarle and Rupert thought, he would only have conceded a limited tactical victory to the English fleet and preserved most of his own fleet. The dismasting of ''Royal James'' was an opportunity that de Ruyter seized, but his attack on Albemarle was still a considerable gamble that might not have succeeded if the rest of Rupert's squadron had attacked him rather than withdrawing to the west.<ref>Fox, p. 268</ref>