Of these two new weapons the submarine was brought earlier to a state of war efficiency, and because it seemed to threaten the security of our island and the power of our navy, it excited the greater apprehension. But the navigation of the air, whether by airship or aeroplane, is now recognized for the more formidable novelty. The progress of the war has proved that within the narrow seas the submarine can be countered, and that the extension of its capabilities on the high seas is beset with difficulties. For aircraft the possibilities are immense. It is not extravagant to say that the 17th of December 1903, when the Wright brothers made the first free flight through the air in a power-driven machine, marks the beginning of a new era in the history of the world. The differences to be looked for in this new era were both over-estimated and under-estimated, according to the temper of those who considered them. Imaginative people, and sentimental people, looked for the speedy fulfilment of Tennyson's vision: For I dipt into the future, far as human eye could see, Saw the Vision of the world, and all the wonder that would be; Saw the heavens fill with commerce, argosies of magic sails, Pilots of the purple twilight, dropping down with costly bales; Heard the heavens fill with shouting, and there rain'd a ghastly dew From the nations' airy navies grappling in the central blue; Far along the world-wide whisper of the south-wind rushing warm, With the standards of the peoples plunging thro' the thunder-storm; Till the war-drum throbb'd no longer, and the battle-flags were furl'd In the Parliament of man, the Federation of the World.