The wall of the inner Ballium separated it from the outer Ballium. The inner Ballinm was a second enclosed space or ground. When a castle had an inner Ballium—which was not always the case—it contained the buildings before-mentioned as being within the Ballium. The Keep, or Dungeon, commonly, but not always, stood on an eminence in the centre; sometimes it was, emphatically, called the Tower. It was the Citadel, or last retreat of the garrison, and was generally a high, square tower of four or five stories, having turrets at each angle, with staircases in the turrets. The walls of these edifices were always of an extraordinary thickness, which enabled them to exist longer than other buildings; and they are now almost the only remains of our ancient castles. In the Keep or Dungeon, the Lord, or Governor, had his state-rooms, which were little better than gloomy cells, with chinks or embrasures diminishing inwards, from which arrows from long or cross-bows might be discharged against besiegers. Some Keeps, especially those of small castles, had not even these conveniences, but were solely lighted by a small perforation at the top. The different stories were frequently vaulted; sometimes they were only separated by joists. On the top of the Keep, was usually a platform, with an embattled parapet, from whence the Govenor could see and command the exterior works. Castles were designed for residences as well as defence. According to some writers, the ancient Britons had castles of stone; but they were few in number, and either decayed or so much destroyed, through neglect or invasions, that, at the time of the Norman Conquest, little more than their ruins remained. The Conqueror erected and restored many castles; and on the lands parcelled out to his followers they erected castles all over the country. These edifices greatly multiplied in turbulent and unsettled times; and, towards the reign of Stephen, they amounted to the almost incredible number of eleven hundred and fifteen. As the Feudal system strengthened, castles became the heads of baronies. Each castle had a Manor, and the Castellain, Owner, or Governor was the Lord of the Manor. Markets or fairs were held in them to prevent frauds in the King’s duties or customs, and there his laws were enforced, until the Lords usurped the regal power, not only within their castles but the environs, and exercised civil and criminal jurisdiction, coined money, and even seized forage and provisions for the garrisons. Their oppressions grew so high, that, according to William of Newbury, there were as many kings, or rather tyrants, as lords of castles; and these lords of castles not only oppressed and despoiled their weaker neighbours, but exercised even royal privileges. Henry II., therefore, stipulated for the destruction of many of them, and prevented the erection of others, except by royal license.