To justify and maintain this line of conduct he should have kept up his fleet, the prestige of which had been so advanced by its victories.

Instead of that, poverty, the result of extravagance and of his home policy, led him to permit it to decline; ships in large numbers were laid up; and he readily adopted an opinion which chimed in with his penury, and which, as it has had advocates at all periods of sea history, should be noted and condemned here.

This opinion, warmly opposed by Monk, was:-- "That as the Dutch were chiefly supported by trade, as the supply of their navy depended upon trade, and, as experience showed, nothing provoked the people so much as injuring their trade, his Majesty should therefore apply himself to this, which would effectually humble them, at the same time that it would less exhaust the English than fitting out such mighty fleets as had hitherto kept the sea every summer....

Upon these motives the king took a fatal resolution of laying up his great ships and keeping only a few frigates on the cruise."[38] In consequence of this economical theory of carrying on a war, the Grand Pensionary of Holland, De Witt, who had the year before caused soundings of the Thames to be made, sent into the river, under De Ruyter, a force of sixty or seventy ships-of-the-line, which on the 14th of June, 1667, went up as high as Gravesend, destroying ships at Chatham and in the Medway, and taking possession of Sheerness.

The light of the fires could be seen from London, and the Dutch fleet remained in possession of the mouth of the river until the end of the month.