It may be remembered that when the hostilities in South Africa commenced, certain experts declared that the new lyddite shells would annihilate the Boers in a very short space of time. The capabilities of the enemy for defending himself had been underestimated by these gentlemen, and the terrible slaughter which was predicted at Paardeberg did not occur owing to the wonderful entrenchments beneath which the Boers and their families sheltered. Any system of entrenchment is of course impossible upon the high seas, and therefore men-of-war have to carry armour plate to protect their sides from the effects of shell and shot. But no sooner had metallic armour been applied to the sides of war vessels than the manufacturers set to work to increase the size and destructive capacity of the shot, and for years past a duel has been in progress between the projectile and the plate; each improvement in the one has led to an improvement in the other, and all the resources of science have been requisitioned to render the projectile more deadly and the plate more impervious to its attack and lighter than before. The advent of the torpedo as an effective weapon of attack brought about the “torpedo-boat,” which was met first by the “torpedo-catcher,” and then by the “torpedo-boat destroyer;” while as protection against the torpedo itself, nets and crinolines have been devised for the purpose of foiling the objects of the attack. A net-cutter on the bows of the torpedo has, however, made its appearance, and it is now considered unlikely that nets will be of much protection to a ship, even when stationary. “The practice of “Submarine Mining” has led to “Counter-mining,” and the adoption of the searchlight on shipboard has caused the invention of a device whereby the rays of light are reflected away from the attacking vessel, thus enabling it to advance unobserved.” The destructive effects of explosive shells have been met by the shipbuilders by the subdivision of the air space of a warship into watertight compartments, and the desire of the enemy’s gunners to inflict injury upon the boilers, the engines, or the propellers, has led numerous inventors to devise a type of warlike craft that shall be almost entirely destitute of armour, but constructed on such a principle-both as to hull and machinery—that she can be raked fore and aft and shot through in all directions without becoming either water-logged or deprived of her motive power.[6] Footnote 6: See “Twentieth Century Inventions,” by G. Sutherland, 1901.