How firm and well made were their roads we know to-day, when, after the lapse of nearly nineteen centuries of traffic, we use and praise them still. They hold in their strong foundations one secret of their maker’s greatness, that the Roman brought to his handiwork the thoroughness inspired by a vision not merely of something that should last a few years or even his lifetime, but that should endure like the city he believed eternal. It was the boast of Augustus, 27 B.C.-A.D. 14, the first of the Roman Emperors, that he had found his capital built of brick and had left it marble; and his tradition as an architect passed to his successors. There are few parts of what was once the Roman Empire that possess no trace to-day of massive aqueduct or Forum, of public baths or stately colonnades. In Rome itself, the Colosseum, the scene of many a martyr’s death and gladiator’s struggle; elsewhere, as at Nîmes in southern France, a provincial amphitheatre; the aqueduct of Segovia in Spain, the baths in England that have made and named a town; the walls that mark the outposts of empire--all are the witnesses of a genius that dared to plan greatly, nor spared expense or labour in carrying out its designs. Those who have visited the Border Country between England and Scotland know the Emperor Hadrian’s wall, twenty feet high by seven feet broad, constructed to keep out the fierce Picts and Scots from this the most northern of his possessions. Those of the enemy that scaled the top would find themselves faced by a ditch and further wall, bristling with spears; while the legions flashed their summons for reinforcements from guardhouse to guardhouse along the seventy miles of massive barrier. All that human labour could do had made the position impregnable. A scheme of fortifications was also attempted in central Europe along the lines of the Rhine and Danube. These rivers provided the third of the imperial trade routes, and it is well to remember them in this connexion, for their importance as highways lasted right through Roman and mediaeval into modern times. Railways have altered the face of Europe: they have cut through her waste places and turned them into thriving centres of industry: they have looped up her mines and ports and tunnelled her mountains: there is hardly a corner of any land where they have not penetrated; and the change they have made is so vast that it is often difficult to imagine the world before their invention. In Roman times, in neighbourhoods where the sea was remote and road traffic slow and inconvenient, there only remained the earliest of all means of transport, the rivers. The Rhine and Danube, one flowing north-west, the other south-east, both neither too swift nor too sluggish for navigation, were the natural main high roads of central Europe: they were also an obvious barrier between the Empire and barbarian tribes.