Until the nineteenth century, however, the federal form of government had given no clear indication of its capacity for holding together great bodies of men, spread over vast territorial areas, in orderly and peaceful relations with one another. The empire of Trajan and Marcus Aurelius still remained the greatest known example of political aggregation; and men who argued from simple historic precedent without that power of analyzing precedents which the comparative method has supplied, came not unnaturally to the conclusions that great political aggregates have an inherent tendency towards breaking up, and that great political aggregates cannot be maintained except by a strongly- centralized administration and at the sacrifice of local self- government. A century ago the very idea of a stable federation of forty powerful states, covering a territory nearly equal in area to the whole of Europe, carried on by a republican government elected by universal suffrage, and guaranteeing to every tiniest village its full meed of local independence,--the very idea of all this would have been scouted as a thoroughly impracticable Utopian dream. And such scepticism would have been quite justifiable, for European history did not seem to afford any precedents upon which such a forecast of the future could be logically based. Between the various nations of Europe there has certainly always existed an element of political community, bequeathed by the Roman empire, manifested during the Middle Ages in a common relationship to the Church, and in modern times in a common adherence to certain uncodified rules of international law, more or less im perfectly defined and enforced. Between England and Spain, for example, or between France and Austria, there has never been such utter political severance as existed normally between Greece and Persia, or Rome and Carthage. But this community of political inheritance in Europe, it is needless to say, falls very far short of the degree of community implied in a federal union; and so great is the diversity of language and of creed, and of local historic development with the deep-seated prejudices attendant thereupon, that the formation of a European federation could hardly be looked for except as the result of mighty though quiet and subtle influences operating for a long time from without. From what direction, and in what manner, such an irresistible though perfectly pacific pressure is likely to be exerted in the future, I shall endeavour to show in my next lecture. At present we have to observe that the experiment of federal union on a grand scale required as its conditions, _first_, a vast extent of unoccupied country which could be settled without much warfare by men of the same race and speech, and _secondly_, on the part of the settlers, a rich inheritance of political training such as is afforded by long ages of self-government. The Atlantic coast of North America, easily accessible to Europe, yet remote