The walls of these Edwardian castles varied from 25 to 40 feet in height and were from 6 to 8 feet thick, or even more, to allow of mural galleries, as at Chepstow, Caerphilly, and Beaumaris. Upon their top was a path called the “allure,” or rampart walk, protected in front by an embattled parapet, and in the rear by lower and lighter walls. Frequently there was a loop in each merlon, and each embrasure was fitted with a hanging shutter, both of which are seen at Chepstow. Where the curtain crosses a ward or projects as a spur, as at Caerphilly and Beaumaris, it was embattled on both faces. The ramparts were usually reached from the adjacent mural towers, but sometimes, as at Warwick, by an open staircase of stone. Occasionally, where a wall is too slight to allow of a rampart wall, it was, in time of war, provided with a platform of wood, like a builder’s scaffold. This seems to have been the case with the city wall of York where it bounds the cathedral garden.
Mural towers vary much in form and size, but are more usually round, or half-round, or half-round with prolonged sides, than square. Now and then they are polygonal, as at Stokesay, Warwick, Cardiff, and the Bishop’s Gatehouse at Llandaff. Stokesay is of the thirteenth century, but usually these towers are later. Mural towers have seldom much internal projection. In Roman works they are usually solid, but in later castles they are sometimes open in the rear or gorge to prevent their being held when taken by the assailants. The towers of Cologne and Avignon are so open, and at the Tower the Byward and Traitors’ Gate towers are closed only with a wooden brattice. The annexed drawing shows the back view of Traitors’ Gate, with the large arch over the water and the timber-work above it.
Where there was an outer ward and a second wall, this was considerably lower than the inner wall, and commanded from it; and the mural towers often became mere bastions, not rising above the curtains. The second ward, besides being too narrow to allow of troops being massed or machines posted for the attack on the inner wall, was traversed by cross walls with gates, so as to isolate any body of assailants who had breached the outer wall. Such cross walls may be seen at Caerphilly and at the Tower.
The barbican was sometimes a mere walled space attached in front of the gateway, as at Carlisle, Alnwick, Richmond, or the Bars at York. Sometimes it was a tête du pont, detached from the main work, and posted at the end of the bridge, upon the counterscarp of the ditch, as at Hawarden, Ledes, and Goderich. At Scarborough it is placed at the outer end of the long raised causeway, which, again, is broken by two drawbridges falling from a low central tower. At Helmsley, as at Caerphilly, the barbican partakes of the character of a horn-work. The Tower barbican, called the Spurgate, is a regular low gatehouse, with flanking drum towers or bastions covering the head of the bridge, and itself protected by a loop from the main ditch. At Bridgenorth the barbican contained a kitchen, ordered to be repaired, 17 Hen. III. At Canterbury the barbican, temp. Ed. II., was used as a prison.
Spelman defines a barbican or “ante-murale” as “munimen a fronte castri aliter ante murale dictum; etiam foramen in urbium castrorumque mœniis ad trajicienda missilia.”
A palisaded embrasure in front of the barbican was known as the “barriers.” They are well represented at the Tower by the stockade covering the entrance.
The drawbridge was an important feature in the defence of a castle. In its most simple form it was a platform of timber turning upon two gudgeons or trunnions at the inner end; when up, it concealed the portal, and when down, dropped upon a pier in the ditch or upon the counterscarp. Its span varied from 8 to 12 feet. The contrivances for working it were various. Sometimes chains attached to its outer end passed through holes above the portal, and were worked within by hand or by a counterpoise. Occasionally there was a frame above the bridge, also on trunnions. In the larger castles the arrangements were very elaborate. Sometimes the bridge was the only connexion between the gateway and the opposite pier; at others the parapets or face walls rested on a fixed arch, and the bridge dropped between them. A fine example of this kind of bridge is seen at the Constable’s Gate, Dover Castle. At Goderich the details are tolerably perfect. The ditch was crossed by a stone bridge, apparently of two arches, but only the outer one is permanent. The roadway of the inner one was a drawbridge. At Caerphilly, in the ditch in front of the main gate, is a large stone pier from which a bridge fell each way. Probably it carried a tower of timber. In Henry III.’s accounts is mention of a brétasche on the bridge of the great tower at Winchester, and of another, covered with lead, upon the new bridge.
The portcullis, the “altera securitas” of the badge of the House of Somerset, always present in the castles of Henry and Edward, was an important part of the defence. It was a strong grating, in the smaller gateways of iron, in the larger of oak, strengthened and shod with iron spikes, and suspended in grooves by two cords or chains, which passed over two sheaves, or sometimes through a single central block, and either were attached to counterpoises or worked, as at the Tower and York gates, by a winch. The grooves are generally half-round, with slightly prolonged sides, 4 to 6 inches broad by from 4 to 7 inches deep. Above, in the vault, is a chase through which the grate is worked. Sometimes the portcullis chamber is a small cell in the wall, as at Rochester keep and Coucy, but in large gateways where there are two or three grates, they are worked in the chamber above. At Linlithgow and Thornton Abbey, where the grate is single, it is carried up within the wall and worked in the second story. Sometimes the grate had no lateral grooves, and must have either hung loose or been steadied by its spikes resting on the ground below. This is seen at St. Briavels and at the upper gate of Chepstow, though never with an outer portcullis. Sometimes grooves are cut for a spare grate, but do not appear to have been armed.
Nothing is more remarkable than the provisions for cleanliness in military buildings. At Ludlow, Langley, and Caerphilly Castles are large mural towers appropriated to garderobes. At Goderich they occupy a broad buttress. At Beaumaris the sewers are of very large size, and run within the main curtain like galleries. Such sewers are often supposed to be secret passages, though the garderobes above, and the character of the outlets below, should correct this notion. At Coyty the filth was collected in an enormous vaulted chamber. The ramparts of the curtains are also usually provided with garderobes.