though it remained a fairly popular sport, and continued to lift gravel from the wharf of the Bun Hill gas-works and drop it upon deserving people's lawns and gardens. There were half a dozen reassuring years for Tom—at least so far as flying was concerned. But that was the great time of mono-rail development, and his anxiety was only diverted from the high heavens by the most urgent threats and symptoms of change in the lower sky. There had been talk of mono-rails for several years. But the real mischief began when Brennan sprang his gyroscopic mono-rail car upon the Royal Society. It was the leading sensation of the 1907 soirees; that celebrated demonstration-room was all too small for its exhibition. Brave soldiers, leading Zionists, deserving novelists, noble ladies, congested the narrow passage and thrust distinguished elbows into ribs the world would not willingly let break, deeming themselves fortunate if they could see “just a little bit of the rail.” Inaudible, but convincing, the great inventor expounded his discovery, and sent his obedient little model of the trains of the future up gradients, round curves, and across a sagging wire. It ran along its single rail, on its single wheels, simple and sufficient; it stopped, reversed stood still, balancing perfectly. It maintained its astounding equilibrium amidst a thunder of applause. The audience dispersed at last, discussing how far they would enjoy crossing an abyss on a wire cable. “Suppose the gyroscope stopped!” Few of them anticipated a tithe of what the Brennan mono-rail would do for their railway securities and the face of the world. In a few, years they realised better. In a little while no one thought anything of crossing an abyss on a wire, and the mono-rail was superseding the tram-lines, railways: and indeed every form of track for mechanical locomotion. Where land was cheap the rail ran along the ground, where it was dear the rail lifted up on iron standards and passed overhead; its swift, convenient cars went everywhere and did everything that had once been done along made tracks upon the ground. When old Smallways died, Tom could think of nothing more striking to say of him than that, “When he was a boy, there wasn't nothing higher than your chimbleys—there wasn't a wire nor a cable in the sky!” Old Smallways went to his grave under an intricate network of wires