Excavated medieval glass from Lacock Abbey, Wiltshire
Hazel Gardiner has recently completed training at UCL Institute of Archaeology (MA Principles of Conservation and MSc Conservation for Archaeology and Museums). She is currently an editor and researcher for the Corpus of Romanesque Sculpture in Britain and Ireland and researcher for the CVMA-GB.
Fig. 1 Naturalistic painted oak leaf on a quarry fragment.
A large group of excavated stained glass pieces has recently come to light at Lacock Abbey in Wiltshire. The abbey, now a National Trust property, was founded in the thirteenth century, so there is the exciting possibility that some of the glass may date to this early period although some pieces (like that shown in Fig. 1) probably date from the early fourteenth century. As excavated window glass provides most of the evidence for the use of stained glass from the smaller religious houses in Britain, the glass from Lacock will add to this valuable resource. Conservation students at UCL Institute of Archaeology in London are in the process of documenting and conserving the glass.
The Abbey
Fig. 2. Plan of Lacock Abbey (from Brakspear 1900). The north wall of the abbey church was retained after the church was demolished. Brakspear’s excavations established the plan of the Lady Chapel and abbey church.
A house of Augustinian canonesses was founded at Lacock in 1230 by Ela, daughter of William, Earl of Salisbury. The abbey buildings, and presumably the glazing, were substantially complete by 1247. In the early fourteenth century a Lady Chapel was added, abutting the chancel on the south [Fig. 2] . A document of 1315 refers to this building work, and mentions the chapel windows, which were to be ‘suitably fitted with iron and glass’ (Talbot 1876, 358).
This document also stipulates that the chapel should be completed within 12 years, suggesting a completion date of c.1327 if work went according to schedule. Repairs and restorations would have been made to the glazing through time, and there may also have been later glazing campaigns, but it seems possible that much of the glass would tally with the above dates.
The abbey was dissolved in 1539 and the church demolished shortly afterwards.
Little medieval glass survives from religious houses in England, and thirteenth century glass is especially rare, so survivals from this earlier period in particular would be of great interest.
Fig. 3. Some of the Lacock Abbey fragments at UCL Institute of Archaeology.
Excavations carried out in 1898 by Harold Brakspear in order to establish the original ground plan of the church may have revealed buried medieval stained glass. Charles Henry Talbot, who owned Lacock Abbey at the time, also carried out at least one excavation prior to 1898 so he too may have found glass. This could account for the bulk of the excavated glass now at UCL [Fig. 3]. An excavation in 2006, of the abbey drainage system, also uncovered stained glass fragments. These were recorded and conserved by the National Trust at that time.
The glass
Fig. 4. Fragment with stylised leaf form.
Elements of the post-Romanesque (c.1200–1260) or Decorated Style (after c.1260) are suggested in the decoration of the readable, painted fragments among the Lacock Abbey glass. Most fragments are currently obscured by excavation soil, so a full assessment is not yet possible.
Fig. 5. Fragment with cross-hatched decoration.
A number of fragments bear traces of stylised leaves, and some have cross-hatching, which could indicate a pre-1260 date, tying in with the earliest glazing campaign. Some fragments are painted with delicate, stylised freehand foliage, although they have no cross-hatching [Figs 4 and 5]. One or two examples display more naturalistic foliage, such as Fig. 1. Cross-hatching was gradually abandoned after c.1260 in favour of clear glass backgrounds, and more naturalistic depictions of foliage began to feature, so it is possible that such examples may date to this later period.
Fig. 6. Grozed fragments among the Lacock Abbey glass.
Many of the fragments are grozed, and some apparently complete geometric shapes survive, while others are asymmetrical and include some complex forms [Fig. 6]. Where glass colour is visible this is usually either because the glass is broken or because deterioration layers have broken away from the underlying glass [Figs. 7 and 8]. Deep blues, greens and reds feature, as does flashed ruby. Other colours include mauve/purple, turquoise and amber, possibly corresponding with the introduction of more naturalistic colours in stained glass in the fourteenth century. There is also much uncoloured glass.
Conservation
Fig. 7. Green glass fragment with laminating iridescent layers.
The Lacock Abbey glass was exposed to atmospheric weathering while in situ, buried for up to 360 years and then stored, following excavation, in uncontrolled conditions for over a century before its acquisition by the National Trust.
Fig. 8. Red glass fragment with laminating iridescent layers.
Much of the glass retains some translucency amidst patches of manganese darkening, and only slight lamination or brittleness. However, at least a third is completely blackened, laminated and alkali depleted to the point that no original glass survives. Many fragments lie somewhere in between, with layers of iridescent or blackened material (and sometimes both) sandwiching a layer of original glass. Most of the fragments retain their painted decoration, even those in the most deteriorated condition. All fragments are obscured to some extent by excavation soil and insoluble salts. Conservation of this fragile material will present many challenges.
Fig. 9. Cleaning test (before cleaning).
Students of the UCL Institute of Archaeology MSc Conservation for Archaeology and Museums programme may carry out investigative cleaning in order to reveal the painted decoration on the fragments as part of the conservation process [Figs. 9 and 10].
Fig. 10. Cleaning test (after cleaning).
The glass could be a valuable research resource. The Corpus Vitrearum Medii Aevi (CVMA-GB), for example, documents and discusses excavated glass as an appendix in its published volumes. As the National Trust has also given permission for analysis to be carried out on the glass, compositional information and deterioration behaviours may be studied, adding to the body of research in this field. Once conservation and any analytical work is complete, the glass will be returned to the National Trust.
Further Reading
Brakspear, H., 1900. ‘Lacock Abbey’, Archaeologia, 57/1, 132–4.
Knight, B., 1996. Excavated window glass: a neglected resource. In: Roy, A. and Smith, P. (eds) Archaeological Conservation and its Consequences. Preprints of the Contributions to the Copenhagen Congress, 26–30 August 1996, IIC, 99–104.
Marks, R., 1993. Stained Glass in England during the Middle Ages, Toronto and Buffalo: University of Toronto Press.
Pevsner, N., 1963. The Buildings of England: Wiltshire. Harmondsworth: Penguin, 254–258.
Talbot, C. H., 1871. On the existing structure of Lacock Abbey, Wiltshire Archaeological and Natural History Magazine, 12, 221–233.
Talbot, C. H., 1876. Agreement for building a chapel at Lacock, Wiltshire Archaeological and Natural History Magazine, 16, 350–359.
Victoria County History, 1956. Houses of Augustinian canonesses: Abbey of Lacock. A History of the County of Wiltshire, 3, 303–316. (http://www.british-history.ac.uk/report.aspx?compid=36542) .
