Against these new weapons the old “wooden walls” were of no avail. Oak and teak, however sound and thick, failed to turn aside the conical projectiles as they had the old round shot and shell. The ponderous missiles would crash clear through, smashing everything in their path, and sending showers of death-dealing splinters right and left. The navy had to protect itself by a revival of the armor with which knights of the middle ages guarded against arrows and javelins and sword-points. By and by, when guns and bullets came, the knights thickened their armor in an attempt to resist these new missiles, until at last it reached a weight too great to be carried, and the whole cumbrous panoply had to be laid aside, and knightly tactics altogether changed. Many persons believe that this history will be repeated in the case of the sea-warriors of the world, which, within the memory of many a grizzled admiral, have changed from buoyant and beautiful ships to grim and shapeless fortresses afloat. [Illustration: THE UNITED STATES FRIGATE “MERRIMAC” BEFORE AND AFTER CONVERSION INTO AN IRONCLAD. Compare with illustration on page 139.] The Americans, fearless of sea-traditions, were the first to propose armor for ships, but the French first practically applied it, building several “floating batteries,” covered with iron 4¾ inches thick, in 1855. The English copied them, in somewhat more ship-shape form; and then the French began boldly to sheathe some of their frigates with iron plates and call them “ironclads.” By this time iron hulls had begun to be used commonly in the British merchant service, but of course the men-of-war’s men, the slowest class of persons on earth to accept any change, insisted that iron would by no means do for war-ships. Nevertheless a few progressive spirits persuaded their high-mightinesses, the Lords of the Admiralty, to try an experiment in building one, and, in 1860, the first iron war-ship was launched and named _Warrior_, while all the old salts wagged their heads and predicted the end of “Britannia rules the waves,” until there wasn’t a really _jolly_ tar to be found from Penolar Point to Pentland Firth. To a certain extent these hardy old growlers were right, though their idea of a remedy was wrong. It proved a failure to build old-style battle-ships of iron or even of steel, or to coat them all over with armor, even when greatly thickened. Not only were they slow and somewhat unmanageable, but by the time one of them had been built with thicker walls than its latest rival, somebody had invented artillery whose projectiles would penetrate it. Ships that are “ship-shape,” that is, possess masts and sails, but are constructed wholly of iron or steel, and more or less heavily armored, have survived, and will always be a part of the world’s navies, no doubt, but their uses will be subsidiary to heavy fighting; and with the disappearance of the wooden sailing line-of-battle ship in the Crimean war and of the iron