The roof of the tower-keep was of timber with an outer covering of lead, and was some feet below the level of the encircling rampart-walk on the top of the outer walls. The rampart-walk had a parapet upon its outer face, which at regular intervals was lowered to form embrasures. The solid portions of the parapet were of much greater breadth than the embrasures: the familiar type of battlemented parapet, in which the embrasures are of equal width with the solid “cops” or _merlons_ between them, belongs to a later date. From the rampart-walk stairs led into the summits of the angle turrets, which were some feet above the level of the parapet. The original arrangement of the roof can be gathered only from the marks left against the inside of the walls. In towers with a cross-wall, like Rochester, each of the divisions was covered, as a general rule, by a roof of more or less high pitch. A central gutter ran along the top of the cross-wall, and side gutters along each of the lateral walls, which were drained through spout-holes made in the outer walls, which carried the rampart-walk. At Porchester, where, as already noted, the tower was heightened, there was originally a high-pitched central roof, with lean-to roofs against each of the lateral walls, and gutters above the centre of each of the two interior chambers. This curious arrangement seems to suggest that the cross-wall itself was added when the tower was heightened, and that the gutters originally were supported by timber struts in the second or attic stage of the tower. When the tower was raised, a flat roof was planned and possibly laid, and, by a curious and unique device, for which it is hard to find an adequate reason, the parapets of the east and west walls were slightly gabled. The present roof, however, is formed in the usual way, with two gables and central and side gutters. In towers without a cross-wall, like Ludlow, Newcastle, and Richmond, the covering was a single high-pitched roof. In any case, the roof was below the level of the rampart-walk, and was not intended to form a free field for the defence of the tower: the occupation of the roof of the tower for purposes of defence was not contemplated until a somewhat later period than that at which the rectangular tower-keep was in general fashion. At Rochester, and probably in many other instances, the inner side of the rampart-walk was protected by a rear-wall, lower than the parapet. The parapet at Rochester was 2 feet broad and 8 feet high: the rear-wall had a breadth of 3 feet, and the rampart-walk of 4 feet. A foot of wall was left for the springing of the roofs and for their side-gutters. The roof at Newcastle was re-laid in 1240; but here and at Dover the insertion of comparatively modern vaults makes the original arrangement difficult to trace. The present roof of Richmond is modern, with a skylight to give light and air to the dark room on the second floor: the height of the outer walls above the roof suggests that the original roof was of unusually high pitch or rose above an intermediate attic. The angle turrets formed elevated platforms, approached from the rampart-walk by stone stairs. Their elevation afforded a greater command of the proceedings of the enemy at the foot of the tower; and their solid construction may sometimes have allowed the defenders to employ them for stone-throwing engines, without interference with the operations of the soldiers on the somewhat narrow rampart-walk.