stoppages, and this is destructive to speed. There is, however, one conceivable means of transit that is not simply frequent but continuous, that may be joined or left at any point without a stoppage, that could be adapted to many existing streets at the level or quite easily sunken in tunnels, or elevated above the street level,[11] and that means of transit is the moving platform, whose possibilities have been exhibited to all the world in a sort of mean caricature at the Paris Exhibition. Let us imagine the inner circle of the district railway adapted to this conception. I will presume that the Parisian "rolling platform" is familiar to the reader. The district railway tunnel is, I imagine, about twenty-four feet wide. If we suppose the space given to six platforms of three feet wide and one (the most rapid) of six feet, and if we suppose each platform to be going four miles an hour faster than its slower fellow (a velocity the Paris experiment has shown to be perfectly comfortable and safe), we should have the upper platform running round the circle at a pace of twenty-eight miles an hour. If, further, we adopt an ingenious suggestion of Professor Perry's, and imagine the descent to the line made down a very slowly rotating staircase at the centre of a big rotating wheel-shaped platform, against a portion of whose rim the slowest platform runs in a curve, one could very easily add a speed of six or eight miles an hour more, and to that the man in a hurry would be able to add his own four miles an hour by walking in the direction of motion. If the reader is a traveller, and if he will imagine that black and sulphurous tunnel, swept and garnished, lit and sweet, with a train much faster than the existing underground trains perpetually ready to go off with him and never crowded—if he will further imagine this train a platform set with comfortable seats and neat bookstalls and so forth, he will get an inkling in just one detail of what he perhaps misses by living now instead of thirty or forty years ahead.

I have supposed the replacement to occur in the case of the London Inner Circle Railway, because there the necessary tunnel already exists to help the imagination of the English reader, but that the specific replacement will occur is rendered improbable by the fact that the circle is for much of its circumference entangled with other lines of communication—the North-Western Railway, for example. As a matter of fact, as the American reader at least will promptly see, the much more practicable thing is that upper footpath, with these moving platforms beside it, running out over the street after the manner of the viaduct of an elevated railroad. But in some cases, at any rate, the demonstrated cheapness and practicability of tunnels at a considerable depth will come into play.

Will this diversion of the vast omnibus traffic of to-day into the air and underground, together with the segregation of van traffic to specific routes and times, be the only change in the streets of the new century? It may be a shock, perhaps, to some minds, but I must confess I do not see what is to prevent the process of elimination that is beginning now with the heavy vans spreading until it covers all horse traffic, and with the disappearance of horse hoofs and the necessary filth of horses, the road surface may be made a very different thing from what it is at present, better drained and admirably adapted for the soft-tired hackney vehicles and the torrent of cyclists. Moreover, there will be little to prevent a widening of the existing side walks, and the protection of the passengers from rain and hot sun by awnings, or such arcades as distinguish Turin, or Sir F. Bramwell's upper footpaths on the model of the Chester rows. Moreover, there is no reason but the existing filth why the roadways should not have translucent velaria to pull over in bright sunshine and wet weather. It would probably need less labour to manipulate such contrivances than is required at present for the constant conflict with slush and dust. Now, of course, we tolerate the rain, because it facilitates a sort of cleaning process....

Enough of this present speculation. I have indicated now the general lines of the roads and streets and ways and underways of the Twentieth Century. But at present they stand vacant in our prophecy, not only awaiting the human interests—the characters and occupations, and clothing of the throng of our children and our children's children that flows along them, but also the decorations our children's children's taste will dictate, the advertisements their eyes will tolerate, the shops in which they will buy. To all that we shall finally come, and even in the next chapter I hope it will be made more evident how conveniently these later and more intimate matters follow, instead of preceding, these present mechanical considerations. And of the beliefs and hopes, the thought and language, the further prospects of this multitude as yet unborn—of these things also we shall make at last certain hazardous guesses. But at first I would submit to those who may find the "machinery in motion" excessive in this chapter, we must have the background and fittings—the scene before the play.[12]