The Development of Material Knowledge 339 maximum rates of travel as held good between Rome and Gaul in the first century a.d. Then suddenly came this tremendous change. The railways reduced this journey for any ordinary traveller to less than forty-eight hours. That is to say, they re- duced the chief European distances to about a tenth of what they had been. They made it possible to carry out administrative work in areas ten times as great as any that had hitherto been workable under one administration. The full significance of that possibility in Europe still remains to be realized. Europe is still netted in boundaries drawn in the horse and road era. In America the effects THE STEAMBOAT CLERIV.ONT. 1807. U.S.A. were immediate. To the United States of America, sprawhng westward, it meant the possibility of a continuous access to Wash- ington, however far the frontier travelled across the continent. It meant unity, sustained on a scale that would otherwise have been impossible. The steamboat was, if anything, a httle ahead of the steam- engine in its earlier phases. There was a steamboat, the Charlotte Dundas, on the Firth of Clyde Canal in 1802, and in 1807 an American named Fulton had a steamer, the Clermont, with British-buUt engines, upon the Hudson river above New York. The first steam-
