The Whitehead torpedo, however, was a new development. It consisted of three parts: first, the “war head,” or foremost section, filled with high explosive which was set off when its sharp nose came in contact with a solid object; second, a round steel compressed-air tank, which took up the midship section; and third, the section to which were attached propellers, vertical and horizontal rudders, and in which there was a powerful engine operated by the compressed air of the midship section. This torpedo could be plunged into the water from a “torpedo tube” and its engine would propel it for four or five hundred yards, while it was kept in a direct line and at an even depth beneath the surface by its automatic rudders. A torpedo boat, then, small, fast, and capable of making a comparatively high speed, did seem to be a dangerous warship. But during the Spanish-American War two Spanish torpedo boats, the _Furor_ and the _Pluton_, were smothered by the fire of the American ships—notably the _Vixen_, which was only a converted yacht—at the Battle of Santiago, and later another type of ship called the “torpedo-boat destroyer” was designed. This new type completely eliminated the torpedo boat. The heavier warships had grown into weird collections of turrets. Turrets carried 12-inch guns, and 8-inch guns, and 6-inch guns, and all of these were sometimes placed on a single ship. Turrets were forward and aft and on both sides, sometimes as many as eight of them. But the 12-inch guns outranged the 8-inch guns, and the 8-inch guns outranged the 6-inch guns, and so the British, seeing the fallacy of these numerous guns of various sizes, decided to build a ship armed only with the heaviest type of naval guns in use and with small guns to withstand torpedo attacks. Thus the _Dreadnaught_ came to be designed. She was the first “all-big-gun” ship, and immediately she changed the design of all line-of-battle ships, or, as they had come to be called by this time, battleships. Incidentally, so great was the effect that the _Dreadnaught_ had, that all the great battleships to-day are called “dreadnaughts,” or, now that they have increased so much in size, “super-dreadnaughts.” [Illustration: AN AIRPLANE VIEW OF THE U. S. S. _LANGLEY_ _An airplane carrier. In order to build the great flying deck the funnel had to be led to the port side, where it projects only slightly above the deck._ ] The _Dreadnaught_ was built in 1906. She is 490 feet long, 92 feet wide, and displaces 17,900 tons. From this will be seen the enormous increase in size that ships had gone through since the introduction of steel. She carried ten 12-inch guns, mounted in five turrets, and in addition to these, originally carried no other guns save twenty-four 12-pounder rapid-fire guns. She could steam at 21½ knots an hour, and the distance she could go without replenishing her supply of coal was 5,800 miles.