Mediæval Military Architecture in England, Volume 1 (of 2)

by George Thomas Clark

Many years ago, about 1683, the then proprietor of the castle, ignominiously known as having removed the upper part of the walls and gutted the interior of the building, discovered that a part of the ground floor rested upon vaults. These he opened and examined, and they are still accessible. The vaults are two in number, built side by side, each 22 feet wide and 96 feet long. They are crossed by a wall 6 feet thick, and thus formed into two vaults of 60 feet and two of 30 feet. The wall between them is 8 feet thick. When discovered they were full of earth, so full that it was evident the contents of the foundations had been heaped and used as a centring, the arch being turned upon the earth or the stones laid upon it. Of one vault the roof is flat, held up by the mere cohesion of the masonry. These vaults had no original entrance, and were evidently works of construction only, not intended to be used. Several breaches were made, so that one vault can be entered from the other; and a breach was also made in the north wall of the keep below the exterior ground-level, through which a good deal of this soil was removed, and thus the cavities admit of a partial examination. The masonry is wholly rude rubble, composed of large pebbles and boulders and fragments of stone, uncoursed, and with a very free use of mortar. The vaults are described as pointed, but the excessive rudeness of the work and the nature of the centring would account for any irregularity in the figure of the arches. To the eye they appear rudely semicircular. That these vaults are of the date of the keep is evident from their relations to the other walls, part of which rest upon them. The present entrance is in the floor of the well-chamber.

For some reason, possibly from an apprehension of defective foundation in a wet sandy soil, it seems to have been thought necessary to take extraordinary precautions against an unequal settlement of the parts of the keep. Hence probably the extensive area, the low altitude of the walls, and the excessive breadth of their foundations. Hence, also, probably, the decision to elevate the floor of the interior above the exterior ground, by the use of vaulting. If such was the cause of these unusual precautions, the result has been perfectly successful, for there is no mark of subsidence anywhere to be seen.

Although a main entrance at the ground-floor level is by no means unknown in Norman keeps, and is found at Carlisle, Ludlow, and Bamborough, it was not usual, and an examination of the present entrance at Colchester leads to the conclusion that it was not originally so here. It is evident not only that the present ornate doorway is an insertion, but that the outer part of the wall above has also been taken down for a considerable height, and clumsily rebuilt. This was done to allow of the insertion of a portcullis. Without this it would have been sufficient to remove the lower masonry only, but the grate required head-room when raised, and to gain this a more extensive alteration was necessary. Immediately above the dripstone are a few courses of ashlar, derived, no doubt, from the old work; but above this the wall is of very inferior uncoursed rubble, very different from the regular courses of stone and tile seen in the wall on either side. When the outer door case was inserted the wall within was also lined with ashlar, and the ring stones of the inner arch and of the entrances to the great staircase were also so cased. Above, the recess into which the portcullis was lifted is of tile, and evidently original; but the floor with the aperture or chase, and the flat back of the recess are later. In all probability there was originally a recess with perhaps a loop where the great doorway now is, and there was certainly a recess above, with probably a loop also. When this door was opened, in the latest Norman period, the original entrance on the first floor, in the north front, was probably walled up, as it still remains. It has been suggested that the great doorway replaced a postern, but posterns in Norman keeps were very unusual indeed, especially at the ground-level, and there seems no reason for supposing one here. Probably when the keep was constructed there was no enceinte wall, but when this was built, the keep became far more secure, and as it was convenient to have an entrance from the town side, the change was made.

There is something to be said for the pertinacity with which this keep has been asserted to be a Roman building. Not only is its design peculiar, but this is also the case with the material employed, and in some degree with the workmanship. The walls, though cased with ashlar on the plinth, and though ashlar is largely employed in the quoins up to the first floor, contain great quantities of the large, square, thick tile so characteristic of Roman work. Moreover, these tiles are mostly whole, as though they had not been employed in an older building, and they are laid in bonding or chain courses, single, double, triple, and even in four courses, with intervening bands of cement stone in small rudely-squared blocks. Sometimes the tiles are laid on edge, sometimes slightly inclined, with here and there a tendency to herring-bone, and the greater part of the interior dividing wall is regular herring-bone, and a very fine example of it. Most of the recesses within the walls were not originally looped, and are round-backed and semi-domed, which is unusual in Norman keeps. Outside the building, high up in the walls, are traces of a number of apertures or perhaps only sunken spaces, about 2 feet 6 inches square. One of these is shown in an early drawing as containing a sun-dial, no doubt an insertion. It has been supposed that these represent tablets with an inscription, but there is no evidence for this. What they were for it is difficult even to guess.

All these features, and some others not actually present, have been adduced to justify the opinions of General Roy, King, and others, in favour of the Roman origin of the building, which is asserted to have been constructed to contain and guard the shrine of a Pagan deity, and afterwards to have been converted by the Normans into a fortress. Such conversions of Roman buildings into mediæval fortresses were, no doubt, common enough in Italy and France, and not unknown in England, as at Pevensey and Porchester, but nevertheless there scarcely seems ground for supposing this building to be Roman, or other than a Norman keep.

The combination of the rectangular plan with angle turrets and intermediate pilasters of slight projection is distinctly and peculiarly Norman. As to the unusual dimensions of the building, in size and height Norman keeps varied considerably, from Clitheroe and Goderich up to Norwich or London. The projection of the turrets also varies from mere pilasters as at Bowes and Scarborough to regular turrets as at Dover and Kenilworth. The half-round projection and the chapel within are indeed rare, being confined to Colchester and London, but no one conversant with the smaller Norman churches could hesitate to class these among them. The spreading plinth is also a Norman feature, and is seen at Norham and Kenilworth. Thick and solid walls at the ground floor are also common. One of the most usual Norman arrangements was to place at one angle a well-staircase communicating with each floor and with the roof, while at another angle was a similar staircase commencing at the first floor.

The Norman entrance, though sometimes on the ground floor, was more usually, as originally here, on the first floor. Neither was it always protected by a forebuilding. Neither Goderich, Clitheroe, nor Chester were so protected. The well in Norman keeps, though often in the wall, was also found in other situations. At Norwich and Castle Rising it was within the area, and at Bamborough. Mural chambers, especially for garderobes, are common in Norman keeps, especially at the first-floor level. Here are three, and a larger chamber, besides the chapel and ante-chapel. The shoots of Norman garderobes usually open on the face of the wall, the lower stone projecting a little to keep the filth clear of it, as at Ludlow and Carlisle. The opening of the flues of the fireplaces upon the face of the wall, close to a pilaster, is a purely Norman device. The use of loops on the first floor, though with large splayed recesses, is also Norman, and a part of the jealous system that pervaded those keeps. Usually it was only at the second floor that the loops became windows. In Norman keeps the floors were almost always of timber, the joists being supported, when necessary, by posts or props, as seen at this day in the Tower of London.

As to material the use of new and clear and unbroken tiles by no means shows a work to be Roman. Those of St. Botolph’s Priory Church were evidently never used before. The only conclusion is that they were manufactured in imitation of those introduced by the Romans. Neither is the mortar that usually described as of Roman composition. It is decidedly white or light in colour, with a great preponderance of sand, so much so as in some parts to have prevented its setting. Where the mortar is in masses it may contain fragments of tile or stone, but there is no trace of pounded brick in its composition. It is generally ill-mixed, and contains large fragments of sea-shells. The putlog holes in size and position are such as are usually observed in buildings of the eleventh and twelfth centuries, though probably not confined to them. The soffits of the vaulting of the staircase and mural chambers everywhere are impressed deeply with the figure of the boards used as centring, or what is called technically lagging. The carpenter’s work in Norman keeps seems to have been very rudely performed, and the rough boards were spread over thickly with mortar to bring them to a surface. This is well seen at Colchester.

Taking all these features into consideration there ought to be little doubt that Colchester keep is a Norman structure, built probably about the close of the eleventh century, by one of the sons of Hubert de Rie.

The keep is the only part of Colchester Castle now standing. The wall enceinte has long been removed, probably about 1650, but its general line to the east, north, and west is indicated by three earthbanks. To the south the ground has been levelled. The entrance from the town was on this side. This was the main gate, but there was also a second. The area thus enclosed appears to have been rather above three acres. Various Roman remains have been discovered within and about this area.