Page:Medieval Military Architecture in England (volume 1).djvu/159

 Of the Shell Keep. 143 also have forebuildings. The keep at Pontefract is very peculiar. The castle covers the table-top of an oval knoll, natural, with precipitous sides of rock. At one end, on the edge of the cliff, is placed the mound, now encased partially in masonry. The masonry begins at the foot of the cliff, as a sort of half-round tower, or rather a cluster of roundlets, built as a retaining-wall. Above, the circle of masonry is completed, includes the mound, and forms the shell keep. The base is honeycombed with passages and chambers, cut in the rock, and partly lined with masonry. In its present condition this keeps exhibits masonry of both Decorated and Perpendicular date, but its substance, as also some of its adjacent masonry, is evidently late Norman. Restormel is rather a round castle than a shell keep, and more Early English than Norman. On the whole, however, it may be classed with the shells. It occupies a natural knoll, and its ring-wall crests the steep slope ; against it are the build- ings, and within is an open court. Launceston, also, though Early English, belongs to the shell type. It has a central round tower, and a concentric wall much lower, a sort of chemise, the space between the two having been covered in with a flat roof. Possibly Montacute, built by the same lord, may have been after the same pattern ; but of Montacute even the ruins have long since perished. The approach to these keeps seems, in its simplest form, to have been by a wooden bridge over the ditch on the side within the castle, and thence by steps up the mound, as at Lincoln, where, however, they are modern, and the ditch is partially filled up. At Tickhill, and at Hawarden, there is a flight of steps just within, and built against the curtain. At Cardiff recent excavations have disclosed the piles of a timber bridge, which crossed the ditch, and may be older than the remains of the Norman keep. Cardiff, however, thanks to the same excavations, affords an excellent example of the more elaborate approach to a Norman shell keep. Here a thick curtain-wall traversed the court of the castle, and crossing the ditch of the mound was continued up its slope ; just within the curtain was a drawbridge across the ditch, beyond which a direct flight of steps led up to the keep. Here, as at Wallingford, the well was on the slope of the mound, just within its ditch. Usually the actual entrance to the keep was by a mere door in the wall, as at Arundel, Lincoln, Tickhill, and Tamworth. At York is a regular gate- house, a part of the shell, which was reached by a very steep bridge, crossing a very formidable wet ditch. It has been mentioned that these shell keeps, and the