Con isboroiigli Castle . 445 The staircase from this stage ends under a sort of hood which stands in and nearly blocks up the rampart walk, leaving a passage only 2 feet 3 inches wide between it and the wall of the battlement. The tower wall at the level of the rampart walk is 1 2 feet 6 inches thick, of which the battlement wall occupies 2 feet, the rampart walk 8 feet, and an inner wall 2 feet 6 inches, within which was the upper or fourth floor. The rampart walk was thus a gallery open above, having the battlement wall outside, and the wall of the upper floor in its rear. The vents of the two fireplaces were connected with this inner wall, and reached its summit by an opening 7 inches by 12 inches, divided by a tile-stone 6 inches thick. This aperture is contained within the base of a chimney-shaft 3 feet 9 inches by 3 feet. This shaft, like the stair-hood, somewhat reduced the breadth of the rampart walk. The upper part is gone. The dividing stones end about 2 feet below the rampart level, above which the vents were combined. The six buttresses rose as turrets above the crest of the parapet. That to the north-west, near the chimney-shaft, and its neighbour westward, contain half-round recesses, round the curve of which are short staircases, opening from the rampart walk, and which probably ascended to small parapeted platforms, now gone. The buttress to the south contains, as at Orford, an oven, circular, 7 feet across, with a segmental arched door 2 feet wide. The two buttresses to the north and north-east are occupied by two cavities, probably cisterns, half-hexagons in plan, and 2 feet 6 inches deep below the rampart wall level. Each would contain about 650 gallons. The remaining buttress, that above the oratory, contains a half-hexa- gonal recess or alcove, the floor of which is 9 inches above the rampart wall. It is 9 feet broad at the opening, 5 feet broad at the end, and 8 feet 8 inches deep. It is covered in with a round-headed vault tapering to fit the plan. The height at the entrance is 7 feet 6 inches, and at the inner end 5 feet 7 inches. There are no loops, but the walls of this chamber and the adjacent parts of the parapet are pierced by a number of holes, about 6 inches high by 5 inches broad. These have been supposed to be intended to carry the floor spars of a bretasche or wooden gallery, though they are small for such a purpose, and there are no holes or corbels below for struts. Moreover, these holes are confined to the buttress over the oratory and the adjacent walls, and are not straight (see plan). They extend, it is true, over the main entrance, but had they been intended for its defence they would probably have been placed with the door beneath their centre instead of below one end of the line. That is, they would have been placed in the two flanking buttresses as well as in the bay
