"Our city of the future will be without smoke, dust or gases from manufacturing plants, and the air will therefore be pure. The streets will be as clean as our drawing rooms today. Smoke will be thoroughly consumed, and gases liberated in manufacture will be tanked and burned. Railways will be operated electrically, all building operations will be effectually shut in to prevent the escape of dust, and horses will disappear from the streets. Out of all these things will come not only commercial economy but bodily health and spiritual joy. As the water is generally pure, all that is needed is more economy in its use. Congestion is intolerable in all the great cities in the world and relief is imperative. It will be found in diverting people in other directions and in changing construction so as to carry more traffic . We may expect, in any event, double tunnels under all the business streets and the utmost use of the present street levels by extensive double-decking and many more overhead transportation lines. Some time the rush in the cities may cease, but I see no signs now of its ceasing, and meanwhile crowding must be dealt with. We need systems of passes around the congested districts. We need still more and mainly to diminish the number of people and vehicles using given areas."