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 ROMANO-BRITISH LONDON been publicly preserved. The solid base of the wall remained until quite recently, almost without change, and indeed a large proportion of this still reposes beneath the houses and streets. Pierced at many points for mains, torn up in places for basements, the old wall yields slowly and sullenly. The earliest description of the wall is that by Dr. John Woodward in 1707,' which is remarkable for its detailed accuracy, and on account of the clear recognition of its being the handiwork of the Romans. Some more recent writers on the subject have ventured to deny this, and to attribute it to a subsequent period, but fuller investigation has firmly estabUshed the view taken by Dr. Woodward. The structure of the wall is that usually followed by the Romans in the south of Britain and in Gaul, bands of stone being bonded at intervals of about 3 ft. with a double or treble row of tiles, the whole plentifully set in mortar and forming a mass of extreme hardness. With a few trifling varia- tions in detail the entire line of the wall from the Tower to Ludgate may be described as uniform. The stone of which it is built is of the same kind throughout, a hard limestone being used for the body of the wall and a ferruginous sandstone for the plinth, both of which would seem to have been brought from the quarries of Kent. The tiles are of the usual Roman character, being large flat bricks of fine close texture, and measuring about iji'm. long, rather less than 12 in. wide, and from iHn, to 2 in. in thick- ness, and are mostly red in colour, but occasionally yellow. All the material was specially prepared and brought for the purpose, the stone is all freshly quarried, there being no re-used material from earlier buildings, and no roofing tiles being employed in the bonds. There is no mixture of other stones than those before mentioned, nor has chalk or septarium been used. The consistent method and uniform character of the wall on the land side points conclusively to its erection under a well-organized plan carried out deliberately at one time. At the time of its construction the surface of the ground was that formed naturally by the gravels and brick-earths of the old Thames. This natural surface is now over'iaid with a great thickness of made soil, the accumulation of subsequent ages, which varies from 8 ft. to upwards of 20 ft. on the line of the wall, while an even greater increase is found further within the boundaries. On the original surface, which was covered only by a few inches of humus, the builders of the wall proceeded to dig a trench about 1 2 ft. wide and from 3 ft. to 4 ft. deep, which was then puddled in with clay and flints tightly rammed down ; occasionally, but not often, ragstone fragments were used in place of flint. A layer of this kind has not been noticed elsewhere in the City, and its object is not very clear, unless intended as a damp course, since in the opinion of modern builders the natural gravel is equally good, perhaps even better, to build on. A thick bed of mortar with small fragments of ragstone, and sometimes flints embedded in it was then laid over the clay puddling ; and above this bed is usually found a thickness of rough ragstone of irregular shape, and often of large size, well grouted in mortar, and forming a footing about 9 ft. 6 in. in width, and in most parts from i ft. to 2 ft. high, but sometimes considerably more ; this layer is, however, at one spot altogether missing (Fig. 22, No. 5). Upon this base rests the wall itself, which above this level is faced with ' Letter to Wren ; Leiand, ///». (Hearne), viii (1711-12). 45