The variety of dangers was beyond anything hitherto recorded, and a certain supremacy in dauntlessness might be claimed by our generation; for men are most easily frightened by risks they are not used to, and every month seemed to bring some new astonishment. The submarine and the flying machine had never been employed in wars before. They were as terrifying to their passengers as to their targets. They brought remote civilians and non-combatants into their field of fire by intention or indifference. The air-raids over London and Paris and the sinking of the _Lusitania_ and various hospital ships horrified the world. The first gas attacks added a new shudder to war. The prolonged and hideous imprisonment in the trenches where men stood to arms in icy mud kept the soul and the body on the rack. The hand grenade came again into fashion with a new deadliness. The machine-gun literally sprayed the field with bullets, mowing men down as with the scythe of death. The tanks were such a prodigy as the first elephants brought into battle. Depth bombs for submarines, land-mines, cannon on railroad tracks, trench-knives, incendiary bullets, barbed wire charged with lightning—it would be impossible to enumerate the new devices for inflicting wounds and death. Yet science could not invent a way to frighten men out of their wits or out of their patriotism. The men in danger simply took what came and held on while the scientists in the rear devised some new defense for the new offense. Nothing was more spectacular than the development of the air-duel and the air-battle by whole fleets of airships. The penalty for bad luck in such an encounter was to fall thousands of feet in a blazing machine. But candidates for these super-chivalrous jousts were innumerable. Naval warfare had its novelties in frightfulness as well. Vessels were subject to destruction by a planted or a drifting mine or by a torpedo shot from an unseen submersible. The destruction of a populous ship was like the cataclysm that annihilates a city. The tortures of patrol duty, the management or the pursuit of submarines, the combats with airships, the protection of convoys, and numberless new-fangled terrors were all superimposed on the ancient dangers of seafaring. Besides the fighting navy there was the mercantile marine charged with the transportation of incredible amounts of supplies and millions of soldiers. With these ships the submarine worked fearful havoc, filling the Seven Seas with hulks and corpses. Yet in spite of all the surprises of science, this war, like all other wars of the past—and it is safe to say of the future—was waged upon the most ancient lines, and its battle-technic was reducible to simple terms.