The best example in England of the kind of tower which succeeded to the rectangular and shell keep of the Norman period is the keep of Coningsborough, which, though containing certain Norman ornaments and details, belongs to the Transition period. It stands on the summit of a natural hill, and forms a part of an earlier _enceinte_ wall, which has been clumsily broken to admit it. The tower, about 70 feet high, is cylindrical, about 50 feet diameter at the base, and 40 feet at the summit, but the cylinder is supported exteriorly by six buttresses of great breadth and bold projection. There is a basement domed over with a central hole above the well. The only entrance is in the first floor, about 12 feet from the ground. The upper floors and the roof were of timber. The staircases are in the wall, winding with it. There are two garderobes, two fireplaces, no portcullis, and in the upper part of one of the buttresses is an oratory. The roof was a cone, but sprang from a ring wall, about 3 feet within the battlement wall and the rampart walk. By this means the tower could be defended without a _brétasche_, which would not have been the case had the roof rested on the outer wall. A similar arrangement may be seen at Marten’s Tower at Chepstow, and at Pembroke. It is not, however, in England that the best examples of these Early English or Transition keeps are to be found. In rectangular and shell keeps England has some fine remains, but in France Philip Augustus carried the new style of building much further, and even now there remain keep towers of that time which have defied time and the madness of the Revolution, and still remain tolerably perfect. The greatest triumph of the period, in this case early in the thirteenth century, is the tower of Coucy, probably the finest military tower in Europe. It is the keep of a castle which is itself the citadel of a town, also strongly fortified. This wonderful work, a cylinder of fine masonry about 98 feet in diameter, and rising clear and unbroken to 180 feet, was the work of Engerrand III., Sieur de Coucy, and the most powerful Baron of his age. The walls are of great thickness, and the basement and upper floors, three in number, were vaulted, each in twelve deep and pointed cells. A fosse, paved and walled, 20 feet broad and 12 feet deep, the counterscarp of which is raised as the wall of a _chemise_, surrounds the base, and protects it from the operations of the miner. A drawbridge, crossing this fosse, leads to the first floor of the tower by its only entrance, which is protected by a portcullis, an interior _meurtrière_, and a stout door. From the entrance passage a staircase ascends in the wall, at first direct, and afterwards as a turnpike, and supplies each floor, reaching finally the ramparts. The basement was the store, and above are state and other chambers. The well, of large size, is in the basement, and each floor has its fireplace and garderobe.