the time this revolution was accomplished, a parallel revolution had transformed the evergrowing cities. Before the development of practical science the fogs and filth of Victorian times vanished. Electric heating replaced fires (in 2013 the lighting of a fire that did not absolutely consume its own smoke was made an indictable nuisance), and all the city ways, all public squares and places, were covered in with a recently invented glass-like substance. The roofing of London became practically continuous. Certain short-sighted and foolish legislation against tall buildings was abolished, and London, from a squat expanse of petty houses—feebly archaic in design—rose steadily towards the sky. To the municipal responsibility for water, light, and drainage, was added another, and that was ventilation.
But to tell of all the changes in human convenience that these two hundred years brought about, to tell of the long foreseen invention of flying, to describe how life in households was steadily supplanted by life in interminable hotels, how at last even those who were still concerned in agricultural work came to live in the towns and to go to and fro to their work every day, to describe how at last in all England only four towns remained, each with many
