On the 8th of June, 1667, Ruyter, the Dutch admiral, sailed out of the Texel with fifty ships, and came to the mouth of the Thames, from whence he detached Vice-Admiral Van Ghent, with seventeen of his lightest ships and some fire-ships. Van Ghent in the same month sailed up the Medway, made himself master of the fort of Sheerness, and, after burning a magazine of stores to the value of L40,000, blew up the fortifications. This action alarmed the City of London; so that to prevent similar mischief, several ships were sunk, and a large chain put across the narrowest part of the Medway. But by means of an easterly wind and a strong tide, the Dutch ships broke through the chain, and sailed between the sunk vessels. They burnt three ships, and carried away with them the hull of the "Royal Charles," besides burning and damaging several others. After this they advanced as far as Upnor Castle, and burnt the "Royal Oak," the "Loyal London," and the "Great James." Fearing that the whole Dutch fleet would sail to London Bridge, the citizens caused thirteen ships to be sunk at Woolwich, and four at Blackwall, and platforms furnished with artillery to defend them were raised in several places. The consternation was very great, and the complaints were no less so. It was openly said the king, out of avarice, had kept the money so generously given to him to continue the war, and left his ships and subjects exposed to the insults of the enemy. After this exploit, Ruyter sailed to Portsmouth, with a design to burn the ships in that harbour; but finding them secured, he sailed to the west, and took some ships in Torbay. He then sailed eastward, beat the English force before Harwich, and chased a squadron of nineteen men-of-war, commanded by Sir Edward Spragg, who was obliged to retire into the Thames. In a word, he kept the coasts of England in a continual alarm all July, till he received news of the conclusion of peace. [Illustration: Water-gate of Tilbury Fort.]