on the Rhone as in Anglesey, but not in the island of the west nor in the mountains of the north. If the Romans had waged the war chiefly to bring the domain of the Druids entirely into their power, this aim was in some measure attained. Beyond doubt at another time all these considerations would not have induced the Romans to renounce the sea-frontier on the north when brought so near to them, and at least Caledonia would have been occupied. But the Rome of that time was no longer able to leaven further regions with Roman habits; the productive power and the progressive spirit of the people had disappeared from it. At least that sort of conquest, which cannot be enforced by decrees and marches, would have hardly succeeded, had they attempted it. [Sidenote: Fortifying of the northern frontier.] [Sidenote: The wall of Hadrian.] [Sidenote: The wall of Antoninus.] Their aim therefore was to arrange the northern frontier appropriately for defence, and to this object their military works were thenceforth directed. Eburacum remained the military centre. The wide territory occupied by Agricola was retained and furnished with forts, which served as advanced posts for the headquarters in rear; probably the greatest part of the non-legionary troops were employed for this purpose. The construction of connected lines of fortification followed later. The first of the kind proceeded from Hadrian, and is also remarkable, in so far as it still in a certain sense subsists to the present day, and is more completely known than any other of the great military structures of the Romans. It is, strictly taken, a military road protected on both sides by fortifications, leading from sea to sea for a length of about seventy miles, westward to the Solway Frith, and eastward to the mouth of the Tyne. The defence on the north is formed by a huge wall, originally at least 16 feet high and 8 feet thick, built on the two outer sides of square stones, filled up between with rubble and mortar, in front of which stretched a no less imposing fosse, 9 feet in depth and 34 feet or more in breadth at the top. Towards the south the road is protected by two parallel earthen ramparts, even now 6 to 7 feet high, between which is drawn a fosse 7 feet deep, with a margin raised to the south, so that the structure from rampart to rampart has a total breadth of 24 feet. Between the stone-wall and the earthen ramparts on the road itself lie the camp-stations and watch-houses, viz. at the distance of about four miles from one another the cohort-camps, constructed as forts, independently capable of defence, with gates opening towards all the four sides; between every two of these a smaller structure of a similar kind with sally-ports to the north and south; between every two of the latter four smaller watch-houses within call of each other. This structure of grand solidity, which must have required as garrison 10,000 to 12,000 men, formed thenceforth the basis of