CAERLAVEROCK CASTLE 131 FIRST PERIOD wards from Murdoch's Tower, there is a perpendicular joint from top to bottom of the wall, showing the junction of the old and new work. The front towers (Fig. 103) measure about 26 feet in outside diameter. Being provided with gun-holes which are clearly original and not inserted, these towers cannot be earlier than the middle of the fifteenth century. In both towers the ground floor was vaulted, but the vaults are now ruinous. They rise from the ground as bee-hive vaults, and seem to have been insertions, as the wall behind, from which they have fallen away, has a finished face on the inside. The towers contain two stories above the vaults, the western one being domed and ribbed at the top. The portcullis-room between the towers (plan and section, Fig. 1 02) is at a sufficient height above the ground to admit of the portcullis being drawn up without the necessity of its coming into the room, which is thus left free for the purpose of working the drawbridge from it. The numerous grooves in the walls for the windlasses and beams connected with the hoisting apparatus are still visible. This room is probably a reconstruction in stone of what in the original castle may have been a wooden hoarding, which contained the apparatus for hoisting the draw- bridge, and also served as a defence over the gateway. The buildings of the fourth period of operations comprise the range against the west wall, which is two stories high, with three rooms on each floor. As will be seen on the plans, the southern rooms do not now exist. The appearance of this range of buildings, with their fine mullioned and traiisomed windows, and with Murdoch's Tower in the background, is shown on Fig. 104. At this period the west curtain wall was heightened by 6 or 8 feet in inferior masonry, of stones, small as compared with those of the wall below, and at the same time a window, the only opening in this wall, was slapped out in the so-called library (Fig. 105). The date of these buildings was probably the first half of the sixteenth century. This portion of the castle shows very clearly how the ancient wall of enceinte was altered and utilised in connection with the extended buildings which were placed against it at a later date. The fifth period of the works comprises the large circular staircase on the west side and the lofty archway adjoining, in continuation of the entrance passage (Fig. 106). The work of this period has blocked up a finely moulded doorway with an old Gothic lintel of the previous period, leading from the south into the circular staircase on the first floor. (See plan, Fig. 105.) The sixth and last period of the history of Caerlaverock comprehends the splendid range of buildings forming the east and south sides of the courtyard built by Robert, Lord Maxwell, probably about the time he .was created first Earl of Nithsdale, in 1620. These buildings are in the Renaissance style, which was then coming greatly into use in Scotland,
