A double-moated Site at Beckenham

A DOUBLE-MOATED SITE AT BEOKENHAM By LILIAN THORNHlLL INTRODUOTION LAND used for the sewage farm was acquired piecemeal by the Corporation of Croydon from 1862 onward, the last acquisition being as late as May, 1951, though over 150 acres were purchased in the first four years, in Woodside, Elmer's End and Penge. The sewage works was closed in 1967, and the area is now to be developed, the reason for its archreological investigation. The sewage farm was never a successful project, for the subsoil is London Clay and the wet sewage would stand in the fields for months without draining away .1 · The problem was aggravated by the fact that the land is low-lying in comparison with its surroundings, the Forest Ridge of Claygate Beds to the north, Addington Hills of Blackheath Pebble Beds to the south, and the ridge plateau of Croydon, the Boyne Terrace, to the west. Drainage is to the north-north-east into the tributaries of the river Ravensbourne. The Chaffinch and another stream to the south flow through the area (Fig. I). The Ordnance Survey 25 in. map of 1861 showed a double-moated site at N.G.R. TQ 354684, standing between 300 and 400 yards east of the county boundary, and the same site is clearly featured on the Estate Map of Thomas Motley, dated 1736, and on another dated 1836. Beckenham Central Library produced a copy of the Field Names Map of Beckenham on a scale six inches to the mile prepared from all then available sources in 1951 by Mr. Edmund K. Roberts in collaboration with Mr. Geoffrey W. Tookey. S o far as concerned the moated site, this Field Na.mes map was based on the estate map of Thomas Motley and therefore added nothing further except as regards the relationship of the site to surrounding fields. On the Thomas Motley map the site was called La Motes, and this name suggested a possible eighteenth-century ornamental feature, though this seemed unlikely since the owner's house and garden stood about a mile and a half away in Beckenham High Street. No other information was available before excavation commenced. Very little study had apparently been done of the area because it was 'border country' between Surrey and Kent. The Archreology Section of Croydon Natural History 1 Information from Mr. J. Lloyd, retired foreman. 145 LILIAN THORNHILL Ii+ ml. / 􀀁 "\ Soul􀀜 Norwood\ MAP 11 Fro. 1. and Scientific Society therefore carried out a limited excavation between 1st July and October 1972. The factors affecting the success of the sewage farm also affected this excavation for the London Clay demanded shoring and the water needed pumps, neither of which could be procured from funds available. Other hazards were, (a) the risk of lead poisoning from the heavy pollution which was present in places though probably not too concentrated where we were working since the Public Health Officer for Croydon advised safeguards but did not forbid it, and the field in which the site lay was a storm-water reservoir,1 and, (b) the open nature of the site which meant anyone could visit and damage. Fencing was put up but eventually abandoned after it was repeatedly thrown into the trench and the posts used to lever out the trench sides. THE EXOA. VATION Yellow clay had been visible a few inches from the top of the drainage channels which covered the whole farm, and it had been thought that when the topsoil was removed, the plan of the moats would be revealed; so two long scrapes were made using a Drott machine. While trying to remove all the topsoil, the ma.chine broke through the yellow clay in one place, revealing a buried land surface beneath. The Drott was of limited use, running into difficulties in dealing with the moats, but we were able to establish their position. The :first scrape of about 45 yards in length, had cut across the corner of the outer moat and Trench I, 10 by 1 m., was set out here. The second scrape, about 76 yards long, at an acute angle to the first, cut across both moats at an angle that later proved to be 96 degrees, Trench II, 10 by I m., was laid across the inner moat (Fig. 2). 146 A DOUBLE-MOATED SITE AT BECKENHAM / / / / / < II FIG. 2. / / / / / / / / I I Trench I was found not to contain the whole of the outer moat and Trench ill was dug 1 m. distant to the west and in a straight line with it. The upper line of the natural infill of the moat was met immediately below the yellow clay. This was of black silt containing many half-decayed leaves, mainly oak, but there were some hazel and willow. A clay tobacco pipe bowl dated by style 1680-1730, was found in this layer, but other than this very little clay-pipe material occurred on the site. Below the black silt was a thick layer of brown peat, containing only leaves and the shells of a.corns. These two trenches were abandoned because it became obvious that the profile they were yielding would be of little value, being shallow and very wide since it was across the corner of the· outer moat and missed the deepest part of it. It was, however, possible to line up the outer lip of the outer moat in the second scrape and confirm the line of this. Trench II across the inner moat yielded a truer picture of the width of the moat. Lying upside down in the peat was the remains of a wide 147 14 LILIAN THORNHILL tin pan, from its handles, probably a preserving pan. As layers below the peat were reached, trouble developed with the top yellow clay sliding on the wet peat into the trench, and when cracks appeared, 'tell tales' were placed where necessary, and threatening sides taken down. On the 1861 Ordnance Survey map and on the 1736 Estate map, the moated site is shown set out as a plantation of trees. The roots and sawn-off stumps of some of these were found in all trenches, so that what turned out to be the top of a decayed plank was thrown on the spoil heap as a rotting root. Oaken beams were uncovered at a depth of 2 · 4 7 m., three in association, and later several more which have been identified by Mr. S. E. Rigold as forming part of the baseframe of a medieval bridge (Plate I). It was hoped to uncover the whole structure and the trench was extended in several directions. Because of the large amount of earth to be moved to reach the timbers, and the need to keep them damp and protected, they became more and more at risk, for the site was open to vandalism. Advice was sought from the Department of the Environment, and we were recommended to cover the timbers with wet clay and back-fill, and the site is to be scheduled. This was done and the trenches were not completed. Trench IV was dug on the same line as Trench II, 5 m. to the south, 10 by 1 m., in the hope of tracing evidence of occupation in the enclosed area of the moat. Under the topsoil was a thick layer of clay with chalk crumbs, and below this, undisturbed London Clay. There is no evidence of the old land surface visible in the other trenches. Trench V, 10 by I m. across the outer moat, was dug on the same line as Trenches II and IV. The same sequence of upper layers was met but no gravel spill, and it was not taken down lower than layer IOb, at the ba.se of which two planks were found lying obliquely on their sides, which could indicate the position of a timber bridge across that moat too. The two bridges would be in line with each other. However, Mr. R. W. Savage is of the opinion that they indicate timber lacing. Medieval sherds were found in association with these timbers also. THE SECTIONS Trench II. Figs. 3a and b Section A is composite owing to collapsing sides. The water-logged nature of the trench and heavy clay made trowelling well nigh impossible. The lowest layers suffered some degree of churning during the necessary bailing out periods. Layer 9 may not have extended so far north, but the step was always crumbling and seemed of the same material. Layer 11 must represent the earliest deposit of silt after the 148 PLATE I Timbers [/au p. 148 A DOUBLE-MOATED SITE A.T BECKENHAM Fros. 3A e.nd B. Sections cutting of the moat and the building of the bridge. Since the timbers were left in situ, it is not known if they rested on the natural London Clay, or not. Layer 10 was only distinguishable from the natural by the presence of sherds, building stone fragments and pieces of tile. Consequently, it is diflicult to establish where it ended. Like the ( natural it turned yellow on exposure to air. Layer 9 was only slightly different in colour from Layers 8 and 10, but less glutinous in texture. These three layers must represent the slo,v silting up of the medieval period of the moat. Layer 8 was greeny-grey until exposed, and only distinguishable from the undisturbed London Clay by the tile fragments it contained. It must be the result of considerable subsidence into the moat, probably at the time when the lacing of the moat gave ,vay. No direct evidence of lacing was found, but it would have been impossible to keep the moat open at all without some strengthening of its sides. Layer 7, gravel, represents an appreciable spill, found only on the inner side of the inner moat. If it had come from the road to the bridge, it should appear against both sides. It could be the result of levelling the inner mound and suggests the interior was capped with gravel (see Discussion). Layer 6 is probably the remains of the road to the bridge. Layer 5 must be the first deposit in a re-cut moat. Apart frgloamz three body sherds of dark grey ware with interior dark green e, nothing was found in it. Layer 4 is the result of the tree planting 149 LILIAN THORNHILL episode. Layer 3 is the final natural infilling of the moat before the site was levelled completely for the se,vage works, using clay containing nineteenth-century material-Layer 2 to fill in the moats. Layer l , topsoil, has formed during use since the 1860s. Trench V Section B gives a much simpler picture. The two timbers were nearer the surface and the moat appears never to have been so deep. The natural was not reached except in a deeper sounding, cut after the section was drawn, to the south of the more southerly timber. Mr. R. W. Savage asserts that the timbers were lying on the subsoil. The only distinction between Layer 10b and the natural being the presence of sherds in the former, there is no certainty without further excavation. To the north of the more northerly timbers in Trench II was an area of hard clay pieces where the hot sun had baked and cracked the exposed surface during the construction of the inner moat. THE POTTERY (Figs. 4-7) Trenches II and V were the only ones in which sherds were found and these were all medieval. At least 33 vessels are represented, 11 of which are jugs of various kinds, one a fine wide bowl and the rest mainly cooking-pots. No shell nor calcined grit-tempered wares were found. The pottery was mainly grit-tempered but some sand-tempered and some Surrey ware also occU1Ted. The earliest is probably represented by the square flanged rims, nos. 16 and 17 (Fig. 5), similar to some found at Addington, Surrey, a style developing about the middle of the thirteenth century. Not much different in date is the baluster jug no. 13 (Fig. 5). These jugs appear to have been made in differing sizes; this example is estimated to be 6 in. in height and similar to two found at Friday Street, London, in the mid-nineteenth century, together with coins (now lost) of Henry III and Edward I.2 One was recovered from a medieval site in Henley Wood, Chelsham, Surrey, excavated by this Society in 1911.3 A rather larger version of the same shape was found at Blossoms Inn, London, together with a thirteenth-century jetton.4 Sometimes these jugs show glazing but no. 13 has none. It exhibits tooling marks where the exterior of the handle was smoothed down, but the interior 2 Arch, JoUJm,, lix (1002), 7. a Report on the liJarthworks at Henley Wood, Ollelsllam, Croydon No.t. Hist, and So. Soo., (1012), 10. 'Antiq. Journ., xii (1880), 178. 150 A DOUBLE-MOATED SITE AT BECKENHAM . -' Fm. 4 (Scale: ¼), shows how the handle was pushed through the walls of the jug and left rough here because of the small diameter. The latest pottery is fifteenth century a.nd represented by no. 2 9 (Fig. 7), a jug with gently swelling body and rod handle paralleled by vessels in the Guildha.ll Museum. A late medieval bowl, no. 5 (Fig. 5) has a well-developed flanged rim, almost 'T' in section, in Surrey ware with gla.zed lower interior. A complete bowl in the Guildhall Museum from Salters Hall, Wallbrook site, pit 64, provides an exact parallel. Much of two fine jugs was recovered, nos. 3 (Fig. 4) and 11 (Fig. 5), both globular, of thin red ware, both with sagging bases and sets of finger impressions at the base of the walls to form a, primitive foot-ring, no. 3 the larger, having five sets and no. 11 three sets. No. 3 has a small pinched spout, a.bsent in the smaller jug. No. 11 is decorated with applied strips forming oblique cordons over the body which is thus divided into panels, alternately painted red and green glazed. It has been suggested because of the clear line between the colours that the 151 LILIAN THORNHILL ] II IS F:!o. 5 (Scale: ¼ ). [J □----,-;;-􀀊 􀀋 f[ 20 4 22 Fro. 6 (Scale: ¼), 152 A DOUBLE-MOATED SITE AT BECKENHAM .,., "" " "'" ,, "-28 ,'/ .,- 􀀆 ,/ 30 ,􀀅' .--I ,,'./ 32 14 29 Fro. 7 (Seale: ¼). 0 \j red slip was applied first, and when dried, it was waxed before dipping into the green glaze, to avoid the colours running. The red is unglazed and flaking badly. No. 3 is almost complete and has a wide strap-handle, pricked for firing. The fabric has a dark core, giving a sandwich effect. The jug was first given a cream slip, then a green glaze which did not penetrate below the handle. A whole group of similar pots, ER 1076 C, were r􀂭covered from Guildhall Car Park during excavations and are now in Guildhall Museum. All the culinary jugs had strap-handles, pricked so as often to leave pimples of clay on the underside. One unusually wide-mouthed jug, no. 26, had red hrematite adhering to the inside, the rim and the handle, and was possibly used for storing hrematite, small flecks of which occurred accidentally on one or two body sherds. Apart from nos. 4, a French pede&tal jug with green glaze, and 13, the jugs are all globular, and five of the eleven are glazed. Three sherds show incised linear decoration, no. 24 (Fig. 6) having combed sets of wavy lines. Other pottery sherds illustrated are jugs, nos. 12, 15, 18-20, mostly gritted ware; cooking pots 22-23, and 27-28, all gritted ware, 153 LILIAN THORNHILL and rims, no. 30, gritted ware, no. 31, hard grey ware and no. 32, off/white ware. The pottery indicates thirteenth- to fifteenth-century manufacture. THE T:IMBERS (Fig. 8a) These were lettered as found and were on the whole remarkably well preserved. Some show signs of re-use as the bridge had been rebuilt at least once. .Although the beams forming the base-frame were in situ, others must have belonged to the fallen superstructure. It is possible that all the still existing beams in Trench II were not found (two more were uncovered during cleaning up operations for photography, before back-filling), and that more remain to be found in Trench V. Furthermore, several of those forming the final base-frame have mortices which were clearly out of use in this phase and were therefore re-used. Three contained oblong-sectioned 'pegs' and another was found loose. Only one tenon was preserved. Any attempt at reconstruction is very problematic. Two empty mortices faced each other on opposing plates as though they were complementary. The remains of two uprights were found, but were not in very good condition and one was destroyed by intruders. A well-cut groove ran the length of beam D and the remains of a plank were set in clay above it, suggesting it might once have stood in the groove. Another piece of planking came to light on the southern side of A on the last day, but it is not known if this also had a grooved timber below it. Timbers A-E were articulated. B was split and massive at the west end; F and L had a mortice each in their northern faces (Fig. 8b). All the timbers were of oak. Bun,DING MATERIAL At the bases of Trenches·rr and V were found pieces of micaceous sandstone and gritstone, some showing tooling and mainly dressed. Four blocks of gritstone had a curved surface and one had mortar adhering on all sides at one end. Tiles were numerous in both moats. All were hand-made, mainly flat or very slightly curved. The two round holes were not always the same distance apart nor equidistant from the top. Decayed daub was found in Trench II and also a part of an iron window catch. SMALL Fnrns l. Clay tobacco pipe bowl, initials 'R.G.' unidentified, on spur. Trench I, layer 3. 154 ·--- .. -. .A DOUBLE-MO.ATED SITE AT BEOKENH.AM ', /􀀞 .. -- - . 􀀟' ,' ' H􀀎----- - - ___ / ! . ... - - ' o---====---=:::21 m I /J .. ...... ------------------------ -- Fxas. SA and B. Timbers 155 LIL!A.1􀀋 THORNHILL 2. Whetstone, slightly curved. Trench II, layer 3. The following note has been supplied by Mr. S. E. Ellis, of the Department of Mineralogy, British Museum. 'This is a "Schist hone" of the common medieval type, i.e. a mica-quartz-schist mullion. These have been traced to Eidsborg, Telemark, Central Southern Norway. This particular specimen is not quite typical of the Eidsborg hones, as it lacks two of their distinctive minor mineral constituents, namely calcite and a uniaxial positive green chlorite, but these are not invariably present. The micas are quite characteristic.' ORGANIC Frnns Only three fragments of bone were recovered, one from Trench II and two from Trench V. A few oyster shells were also found in the inner moat. The peat contained oak, hazel and willow leaves, shells of hazel nuts and acorns. DISCUSSION The original topography of the area would appear to have been destroyed by the measures taken in the 1860s to provide level surfaces for the sewage farm. As stated in the introduction, gravel beds are found on the hills to the north, south and west. Anerley Hill has a very interesting profile and drops do,vn towards the south in five stages, separated from each other by rises. If these were river terraces, the stages would be separated by flat surfaces not inclines. It is suggested that these stages were the result of successive falls from the original heights of the Forest Ridge in geological times. This ridge is of London Clay capped by gravel of the Claygate Beds, and if each fall had carried its own capping, this would account for the persistence of the inclines. The fifth drop terminates in the neighbouring cemetery. Patches of Blackheath Pebble Beds are found bordering Long Lane to the south, so that gravel could have occurred on the site associated with either of these sources. The field names shown on the eighteenth-century map as drawn by Roberts suggest a gently rolling landscape, for several fields are called hursts which can mean a wooded hill, and another adja-0ent to the moat is called W a