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