Still the monarchs of the Plantagenet race had ships of their own; but their chief notion of keeping up a navy was by laying taxes on the sea-ports, on commerce, and on the fisheries, thus crippling the surest means by which a fleet could be maintained. The chief naval events of the intermediate reigns have been described in the preceding chapter. John, we are told, had a naval establishment of ships and officers, with certain boards for its government. He had not many vessels, however, as he chiefly depended on the Cinque Ports to furnish him with ships, while he laid an embargo on merchant-vessels in case of necessity; and turned them into ships of war. He must have had a great notion, however, of keeping up the dignity of England on the ocean, as he passed an ordinance that all ships should lower their topsails to the English flag; a custom which was preserved for many centuries. Foreigners, however, did not always show themselves willing to conform to the custom, and it was more than once the cause of quarrels between England and other nations. Still, even at the present day, English men-of-war do not salute foreign ships in that or any other way, unless the latter pay the compliment to them first, or at the same time. Philip Augustus of France having attacked his ally, the Earl of Flanders, the king fitted out a numerous fleet, which he placed under the command of the Earl of Salisbury, giving him directions to destroy rather than to capture any of the enemy's ships. The Earl of Salisbury observed his instructions, and followed the movements of the enemy, waiting for an opportunity to bear down upon them. The French ships, amounting to more than nine hundred sail, moved slowly over the sea, he watching them vigilantly, and bearing the reproaches of his officers, who thought him deficient in courage. On the third day a slight storm having thrown the French fleet into confusion, the earl bore down upon them. The winds had so terrified the French that they were in no condition to stand before a furious enemy. The English, who were far better sailors, were in high courage, and so furiously assaulted the French ships that in a short time upwards of a hundred were sunk, many more running on shore, while scarcely forty got back to the ports of France.