Annual Inspection of the Thornham Parva Retable

The Thornham Parva Retable. © C. Titmus. With many thanks to the wardens of St Mary’s Church, Thornham Parva.

The Thornham Parva Retable was made circa 1330-1340, and is one of a very small number of such objects known to survive in Britain. It is a remarkable and important extant medieval English religious painting and sits behind the altar at the east end of the chancel in the tiny church of St Mary, Thornham Parva, Suffolk. In February 2019 a team of staff, students and interns from the Hamilton Kerr Institute drove to the church to conduct an inspection of the Retable, a duty performed annually since its extensive conservation treatment at the Institute almost 20 years ago.¹ While we were in the area we paid visits to two other churches, Yaxley and Eye, to see their rood screens; a genre of late medieval decorative painted church furniture with over 500 survivals in East Anglia.

The church of St Mary, Thornham Parva. © Hamilton Kerr Institute

The Thornham Parva Retable

The Thornham Parva Retable is a horizontal panel some 3.9m long and 1.1m high, divided with columns into 9 sections which depict respectively, from left to right, Saints Dominic, Catherine, John the Baptist and Peter, the Crucifixion with the Virgin and St John the Evangelist, and Saints Paul, Edmund, Margaret and Peter Martyr. A Retable is an altarpiece; a panel decorated with devotional images that would have been positioned behind the altar and formed the backdrop to the liturgy. This Retable is thought to have been commissioned by the Dominican Priory at Thetford, Norfolk, and the depicted saints point to a Dominican patron. The Retable’s considerable size and quality are indicators of origins in a large and wealthy religious house. Stylistic similarities have been noted between the images on the Retable and designs on medieval glass fragments excavated from Thetford Priory ruins. The Cluny Frontal (Musée National du Moyen Age, Paris) has been identified as the companion piece, showing scenes from the life of the Virgin, which would have been positioned at the front of the altar table. The same craftsmen collaborated on both pieces.

Thornham Parva
The Retable inside the church, viewed through the Medieval rood screen. © L. Wrapson.

The Retable is constructed from oak, and its straight grain indicates that it was imported from the Baltic, which is common in panel paintings in England from the Middle Ages to the Early Modern period. It also had a frame originally that would have been affixed to the support prior to painting and decoration. The original frame on the Cluny Frontal gives some indication of what its appearance might have been here. The panel is has a ground of chalk bound in animal glue, and analysis has suggested that the chalk may well have geological origins near Thetford. The design for the painting is drawn out onto the chalk layer, and some of this drawing was executed in the bright red pigment vermilion, which is unusual. Next, a layer of lead white in oil was applied. The sumptuous background decoration, comprising squares of gilded ‘tin-relief’ designs, would have been applied before the figures were painted. The name ‘tin-relief’ derives from the technique for this form of decoration. The reliefs are made of putty containing a mixture of pigments in resin and oil, which was pressed into a mould lined with tin-foil as a release layer. A variety of moulds were used here. This decorative technique is particularly interesting because it was to feature prominently in the later medieval rood screens of East Anglian churches. The figures are painted in a bright array of pigments including lead white, blue azurite, red and yellow earth pigments and copper-based greens. These were also mixed and blended to give other colours and tones. A greater range of colours and effects was created by glazing over the top with transparent pigments like red lake and the copper green pigment verdigris.

Detail of lamb motif in tin relief. © Hamilton Kerr Intitute

Rediscovered in 1927 in Thornham Hall, where it existed in three sections, the Retable was installed in St Mary’s and throughout the 20th century was transferred to several places in the country at various times, escaping war, travelling to an exhibition in France, and receiving intermittent conservation treatments to secure the paint and re-gild the background. It came to the HKI between 1996 and 2001, where, with funding support from the National Heritage Memorial Fund, English Heritage, World Monuments Fund and Samuel H Kress Foundation, it received full conservation, including consolidation (re-adhesion of flaking paint and ground), cleaning and removal of multiple and thick layers of overpaint, discoloured resin varnishes and previous wax-resin adhesives. Extensive research and technical analysis were carried out, including dendrochronology, X-ray and pigment analysis, and reconstructions to further explore certain aspects of the technique. As a result of the treatment, the majority of the paint represents the original medieval scheme and, despite the areas of damage and paint loss incurred from iconoclasm and neglect, the painting is in exceptional condition for its age. The conservation also involved monitoring and improvement of the environmental conditions within the church and provision of a protective enclosure for the Retable, and the work continues in the form of an annual inspection. These are all examples of what is known as preventive conservation.

Preventive conservation and the Thornham Parva Retable

Preventive conservation is a branch of conservation and preservation that involves creating and implementing policies to passively ensure the longevity of cultural heritage. The Canadian Conservation Institute (CCI) has identified ten “Agents of Deterioration” that act as an outline for what might harm cultural heritage.² Therefore, preventive conservation is concerned with environmental monitoring, documentation, integrated pest management, proper handling policies, implementation of security measures, and protection from fire, water, pollution, and too much light. Some of the actions a conservator might take to mitigate the potential harm include periodic condition assessment of objects and their environment to keep a record of changes, and to be alert of any changes that might be a detriment to the preservation of a work so they may be mitigated. All of this work ensures the long-term protection of works of art, including pieces like the Thornham Parva Retable.

With this in mind, students and interns led by Dr Lucy Wrapson, all from the HKI, set out to Thornham Parva to do a yearly condition check of the Retable and lightly clean its surrounds.  The Retable is set on the altar in a specially-made case, which protects the piece primarily from dust, changes in temperature and relative humidity, and possible theft or vandalism. The case was integrated into the structure of the nave so it was as unobtrusive as possible and still allowed the congregation to us it as it was intended.  As part of our inspection, we were able to lower the glass in front of the Retable and get a close look using flashlights and head loupes. This way, we were able to look for any flaking or other damage that might have occurred over the course of the last year.  Fortunately, there was no change in the paint and ground layers, except a bit of dust build up, which we very gently removed with a soft brush. Cobwebs around the case were also vacuumed up, as well as some salt efflorescence that perennially emerges between the floor and the wood panelling at the bottom of the case on the north side. While the source of this salt is not clear, it is important it is monitored and documented, as a change in the pattern can be an indication of something amiss with the building envelope. We also cleaned the inner and outer faces of the glass of dust and smears, so that the colours and details of the paintings can be fully appreciated.

Dusting the case with the glass partly lowered. © Hamilton Kerr Institute.
Salt deposit on the floor at the foot of the frontal. © Hamilton Kerr Institute.
Carefully cleaning the outer and inner faces of the glass, half-lowered, which required getting into some interesting positions! © Hamilton Kerr Institute.

The stable condition of the painted Retable speaks to what passive measures can do for the preservation of cultural heritage. For example, the red lake pigments are still very bright in the painting, which is very rare for an object of this age. These bright colours possibly suggest that the Retable was protected from bright light, which would have faded this fugitive pigment. Similarly, the wooden panels have been largely spared from damage by wood-boring insects, so they are still structurally sound. This special object was clearly valued by the community that had it made, and its stewards over many hundreds of years, including the current Thornham Parva community. The conservators at the HKI, in conjunction with the current church community, are able to use the principles of modern preventive conservation to continue to maintain the Retable for future generations.

Two Suffolk medieval rood screens

While we were in the area we had the opportunity to visit the rood screens in the churches of the nearby village of Yaxley, and the town of Eye. ‘Rood screen’ is the generic term that refers to the composite divisional structure that separated the chancel from the nave in a medieval church, and East Anglia contains the densest concentration of this type of object Europe-wide. Most screens that survive were constructed between the early 14th and mid-16th centuries, and they were known by the names rood loft, candlebeam, perke, and a host of other interchangeable terms. They were composite structures generally consisting of the dado (the lower part, bearing images of saints – this is usually the only part that survives in the church) and an upper traceried part, surmounted by a beam bearing the rood group (a wooden cross and figures of the Virgin and St John the Evangelist). The saints and angels depicted on screens acted as intercessors through whom the prayers of the local communities reached God. Screens were the work of multiple workshops that included carpenters, painters and sculptors, some of whom engaged in multiple crafts. They also would often have been fabricated piecemeal, with multiple donations, usually in the form of will bequests, for the construction or decoration of separate parts of the structure – for example, an individual or a local guild might dedicate a sum in their will towards the painting of their name saints. Many screens have been lost or severely defaced in bouts of iconoclasm following the Protestant Reformation and during the English Civil War. Of those that do survive, the work of certain craftsmen or workshops has been identified on a number of screens, which was a focus of Dr Lucy Wrapson’s PhD.³ Click here to view the blog post about the conservation of the rood screen in St Matthew’s church, Ipswich, in 2016.

St Mary’s church in Yaxley is a mainly 15th-century structure with a magnificent porch featuring flint flushwork, and a roof with carved angels and other figures. There is also a doom painting above the chancel arch. There is beautiful gilded tin relief to be seen on this screen, including a charming little face with a sticking-out tongue, and the saints’ garments are decorated with intricate brocade patterns. We looked closely at the carving and carpentry, which features intricate designs and is the output of the same group of craftsmen who worked on the screen at nearby Eye.

The rood screen in St Mary’s church, Yaxley. © L. Wrapson.
Detail of St Mary Magdalene on the rood screen at Yaxley. © L. Wrapson.
Detail of face with tongue sticking out in tin-relief background at Yaxley. © Hamilton Kerr Institute.

As Eye was a wealthy wool town in medieval times, the church here was notably large and grand. In this screen, the dado is medieval and most of the rood loft and beam with rood group is the early 20th-century work of Ninian Comper. The painted saints on this screen are very different in style to those on the Yaxley screen, being much more generic and less refined (but still charming). Here the saints were generally arranged male-female alternately, whereas those on the Yaxley screen were mostly female. The tin relief designs in the background here are much simpler than at Eye. Lucy highlighted the similarities of the carving and tracery designs on the spandrels and in the lower dado with the Yaxley screen and pointed to the remains of a dedicatory inscription on the loft.

The rood screen in the church of St Peter and St Paul, Eye. © L. Wrapson.
Detail of St Agnes on the rood screen at Eye. © L. Wrapson.

Preventive conservation measures are important for the protection of rood screens, although sadly many exist in churches with uncontrollable humidity, temperature and light levels and are deteriorating as a result and suffer damage from insects such as deathwatch beetle. The visits we made today were an insight into the treasures that survive hidden in East Anglia’s churches, and the story of the Thornham Parva Retable exemplifies what is possible with the enthusiasm, support and collaboration of people with diverse interests, knowledge and professional skills, and what might be achieved for rood screens in the future.

Katharine Waldron and Ellen Nigro, 1st year Post-Graduate Interns (2018-2020)


1. Massing, A., ed., The Thornham Parva Retable. Technique, Conservation and Context of an English Medieval Painting (Hamilton Kerr Institute, University of Cambridge and Harvey Miller Publishers, 2003).

2. Canadian Conservation Institute, ‘Agents of Deterioration’. Retrieved from, February 2019.

3. Wrapson, L., ‘Patterns of Production: a technical art historical study of East Anglia’s late medieval screens’ (PhD this, University of Cambridge, 2013).

About the Authors:

Ellen Nigro graduated from the University of Delaware in 2013 with a B.A. in Art Conservation and Art History. After gaining internship experience through projects at the Freer and Sackler Galleries, Shelburne Museum, Villanova University, and the Chrysler Museum, she entered the Winterthur/University of Delaware Program in Art Conservation (WUDPAC). Her projects in the program included developing a consolidation strategy for a matte, underbound, 19th-century Thai panel painting, and completing a technical study on it. She earned her M.S. from WUDPAC in 2018 after her third-year internship at the Royal Picture Gallery Mauritshuis as the Fulbright-American Friends of the Mauritshuis Intern.

To contact Ellen:

After completing a BA in History of Art at the University of Warwick, Katharine graduated from The Courtauld Institute of Art in 2018 with a Postgraduate Diploma in the Conservation of Easel Paintings. One of her projects involved the conservation and technical research of a modified 17th-century harpsichord lid, which led to her third-year dissertation project on historical copper green glazes. She has worked for Katherine Ara Ltd. and as an intern with the National Trust, the House of Lords, the National Maritime Museum, the V&A, and the RCE in the Netherlands as a Zibby Garnett scholar. Among her current projects at the HKI, Katharine is involved with research into the pigments and techniques of church polychromy in East Anglia.

To contact Katharine:

Conference Review – Migrants: art, artists, materials and ideas crossing borders. Hamilton Kerr Institute, 15th-16th November 2018.

Final DesignThis two-day interdisciplinary conference, hosted by the Hamilton Kerr Institute and held at the Murray Edwards College, University of Cambridge, featured talks that explored how artists, conservators and their materials, ideas and techniques have crossed borders from antiquity to the modern day (click here for the full programme). The artworks discussed were diverse, not only paintings but sculpture, mosaics, textiles, architecture and archaeological finds, and the speakers addressed issues of war, trade, exploitation, individual personalities and the transmission of information across localities and time. It was an opportunity to bring together people from different countries and cultures, and share research from a number of disciplines in the arts, sciences and humanities.

Dr Kristin Kausland (Norwegian Institute of Cultural Heritage Research/Hamilton Kerr Institute) began the first session, ‘Art and Artists’, with her talk on the manufacture of Scandinavian altarpieces in the late Middle Ages, considering the contribution of immigrant Northern German artists to their fabrication, as well as the import of objects. Presenting results of detailed technical study of several altarpieces, she highlighted the amalgamative nature of these superstructures, clues in regional techniques such imitation gold, and the use of model books through generations of craftsmen. We are greatly looking forward to welcoming Dr Kausland at the HKI in February as she carries out her post-doctoral research.

Jessica David, representing the Yale Centre for British Art and colleague Edward Town, presented research exploring the work of the 16th-century artist Netherlandish Daniël van den Queborn, who served a British client base formed of military men who fought in his homeland during the Dutch Revolt. From in-depth examination of his works, the authors built an interesting portrait of a versatile artist who, in his role as ‘court’ painter to the House of Orange, built his career on diplomacy. Records from the RKD database were consulted, a resource cited as an example of instantaneous accessibility to knowledge that enables us to virtually traverse geographical distance and time today.

Javier Grossutti (Swinburne University of Technology) introduced us to terrazzo, a form of mosaic flooring seen in many buildings in the UK and Italy. Grossutti led us from the craft’s 16th-century origins in the Italian town of Friuli and its development in the 19th century under Pietro Mazzioli, who travelled to England and established a factory in London. We were given a sense of the sheer scale of the industry from the pictures of familiar places such as the National Portrait Gallery, but also buildings in other British towns and cities.

Pia Gottschaller (The Courtauld Institute of Art) discussed the Asociación Arte Concreto-Invención (AACI) movement in Argentina, Uruguay and Brazil from the 1940s to the 1960s. She set out a vivid picture of the artistic network established and highlighted the artists’ experimentation with new media, enabling them to communicate their ideas in a new way. Gottschaller reminded us that the travel of the artists in the 20th century, when journeys were expensive and long, might be considered just as striking a feat as Queborn’s establishment of an international client base in the 17th. On the other hand, Gottschaller also noted that these factors, and language barriers, continue to inhibit communication today, contributing to the dearth of scholarship on Concrete artists.

Beginning session 2, ‘Conservators and Conservation’, Dr Caitlin O’Grady (University College London) talked about the use of wax in the preservation of archaeological artefacts in the early 20th century, centring on the work of Sir William Matthews Flinders Petrie who led new developments in the preservation of excavated artefacts. O’Grady showed how the use of wax in the field became a recognised practice, and how the paucity of documentary evidence means that now, much of the information regarding the use of wax must come from the objects themselves. She also defined the role of ‘boundary work’ between archaeologists, scientists and curators in the spread of knowledge about such techniques for preservation.

Katya Belaia (National Trust) and Valeriia Kravchenko (Museum of Ukrainian Art) spoke on the history of conservation in the Ukraine and the issues faced by conservators working in a Soviet society. They highlighted the work of conservators who worked in the Soviet era to preserve objects that were forcefully disregarded at the time. It was particularly interesting to hear about the structure and content of conservation training programmes in the Ukraine today, where there remain restrictions against conservators working on a freelance basis. It was remarked that destruction of cultural property is still seen there today with attempts to abolish remnants of the Soviet era.

Rebecca Rushfield (New York City and Associate Director, FAIC Oral History Project) presented on the immigration of European conservators to the US from the early 20th century to today. She drew on information from the Oral History Project, an initiative by the Foundation of the American Institute for Conservation, begun in 1975 and containing transcripts of interviews with conservation professionals. She demonstrated the of role of professional networking in recent decades in enabling European conservators to take up posts in the US, but also the challenges experienced by the conservators who made the move, regarding visas, work permits and cultural transitions. She provided a glimpse of the wealth of material gathered by the Oral History Project, with the individual experiences of the conservators themselves.


The third session, ‘Art and Conflict’, opened with Morwenna Blewett (Worcester College and Ashmolean Museum, University of Oxofrd) on the subject of the British Intelligence Objectives Sub-committee (BIOS), composed of British government officials who were sent to Germany after the Second World War to report back on technical and scientific industries, including the manufacture of artists’ materials. Consulting information from manufacturers’ archives, including that of Winsor and Newton at the HKI, Blewett described how the advances of German industries were exploited in the years following the war through the internment of German scientists in Britain and their employment at institutions such as the National Gallery. The talk highlighted a striking example of forced migration that is rarely considered in the context of the horrors of the war.

Dr Roderick Bailey (Wellcome Unit for the History of Medicine, Universityof Oxford) gave insight into the work of another British investigative group following the Second World War, the Monuments, Fine Arts and Archives (MFAA) sub-commission, who supported and educated the Greek authorities in the protection of ancient monuments such as the Parthenon and other buildings in the Acropolis, which had suffered many forms of damage during the war. However, illustrating the war damage sustained by a Jewish synagogue, Bailey also highlighted the limits of their work and the implications for the heritage of certain other cultural communities in wartime Greece.

Charlotte Bank (Art historian and independent curator) discussed the work of Syrian artists throughout the world, displaced by war from their homes. Through several case studies of artworks exhibited by the artists in several European cities, Bank showed how these individuals have used art as a platform to express their responses to their experiences and connect with their new cultural environments. However, she also warned of the ease with which viewers can become blind to all other interpretations of their work. Through highlighting their unique experiences and personalities, the talk served as a reminder to avoid the exploitation and pigeonholing of Syrian refugee artists as ‘war artists’.

On the second day, Dr Eckart Marchand (Warburg Institute/International Research Project Bilderfahrzeuge) kicked off the first session, ‘Materials and Techniques’, with his talk on the subject of Plaster of Paris, focusing on the Lucchinese figurinai, a community of peripatetic craftsmen from Barga who made popular plaster figurines (‘formatori’) and journeyed with their wares to Germany and America, where the craft gained particular prominence in the 19th century.  This was a remarkable example, recalling the mosaics discussed by Grossutti, of how a small craft local to a particular geographical area can spread and become an international phenomenon, its identity evolving along the way.

Felicia Gottman (Northumbria University) spoke about the role of migration within the cotton industry in 18th-century France, focusing on the career of textile manufacturer Jean-Claude Flachat, who imported workers from the Levant and expanded his industry exploiting the knowledge and technologies they brought with them. Gottman considered Flachat’s enterprise in the context of the Actor-Network Theory, focusing on the role of ‘non-traditional agencies’ – the cotton, the technologies, and the experiences of the workers – through which knowledge was transferred and developments ensued in cotton manufacture and trade.

Jenny Bulstrode’s paper (University of Cambridge) explored the many identities of copper, ranging from its elemental properties to its geographical source in the mines of Cornwall and Australia, its manifestation as trade tokens and ship hull sheathing, and its use in tribal masks. The talk demonstrated how copper has been exploited historically to advance technologies and cultures, and the distances the material has travelled between countries, from the depths of the Earth and through time. The talk highlighted that migration can refer to the changing identities of a given material as it migrates itself through time and between cultures.

Jacob Simon (National Portrait Gallery) discussed the impact of migration on the transfer of artists’ materials between countries from the 18th through to the 20th centuries. Simon documented the competition between manufacturers as materials were exported and supply chains for British and other European manufacturers established in several countries. He conveyed the complex exchange of influences and materials between British and foreign suppliers, which also impacted on where artists settled and how they chose to develop their art. Ultimately, Simon concluded that this last consideration comes down to the three factors of material quality, permanence, and price.

After lunch on the second day we had an excellent introduction to the collection of paintings at Murray Edwards College, which showcases over 500 works and represents the second largest collection in the world of contemporary women artists. Many of the paintings were on display around the college and we had a wonderful opportunity to explore.

Opening the final session, ‘Transmitting Ideas’, Karen French, representing the Walters Art Museum and colleagues Christine Sciaccia, Glenn Gates and Hae Min Park, gave a talk on the late medieval Ethiopian religious paintings currently undergoing technical research in a collaborative project at the Walters Art Museum, Baltimore. Describing the popularity in Ethiopia of religious imagery and cults from the Western Christian church from the 15th century, French discussed the exchange of ideas with Italian painters brought to the country, focusing on the art icon painter Fre Seyon. French pointed out examples of the influence of Italian painting on aspects of the iconography, but also revealed interesting divergences regarding the materials and techniques.

Julia Brandt and her colleagues Isabel Wagner and Corinna Gramatke (Technical University Munich) presented new research, currently in progress, on the art of the Jesuits who populated South America in the 17th century, imposing their religion and art on the indigenous Guarani people. The cultural influence appears to have been strictly concentrated in one direction, unlike the exchanges featured in some of the other talks. This example of art and culture enforced on the people was an interesting comparison to the conscious decision to pursue western religious doctrine by the Ethiopian emperors discussed in the previous paper.

Esmee Schoutens and her colleagues Rosa Mulder and Janneke Sif Rutten (VU University, Amsterdam and University of Leiden) presented collaborative research undertaken recently into the geographical representation of artists in the collections at the Stedelijk Museum. Using digital software to collect and organise the data from the collection from 1896 (the Museum’s foundation date) to 2003, trends were noted that showed, for example, that artists from Eastern Europe were well represented but those from the Middle East were not. This led to more complicated questions including whether some artists’ work only appears in the collections because they were working at that time in a ‘geographically represented’ region. This ongoing research demonstrates the information that can be gleaned from a study of such a significant world-class collection of modern and contemporary art.

The opportunities for discussion, led excellently by all of the chairs – Vicky Sutcliffe and Sally Woodcock (Hamilton Kerr Institute), Dr Alexander Marr, Professor Simon Schaffer and Professor Mary Laven (University of Cambridge), and Dr Abbie Vandivere (Mauritshuis/University of Amsterdam) – resulted in the emergence of notable links between even the most divergent talks. We saw examples of migration across vast geographical distances and across time. We were shown how migrants have often been perceived or conveyed throughout history as a ‘package deal’ comprising the labour, experience, skills and technologies of their craft. It was emphasised how migration is rarely in a single direction, with cultural exchanges taking place and the existence of complex networks of artists and industries established between different cultures. Also demonstrated were the results of when migration is prohibited or enforced upon peoples, and we came to appreciate the many different situations that have led to migration – voluntary or otherwise – by artists, crafts and materials over the centuries. Perhaps most compelling was the revelation of the individual stories of the artists and innovators that have travelled throughout history; the anonymous voices known predominantly through artefacts and rarely acknowledged in the wake of more prominent historical figures.

Overall, at a time when words and phrases such as ‘take back control’, ‘borders’, and ‘independence’ are in constant repetition, and when migration is so often portrayed as a ‘good’ or ‘bad’ phenomenon, it was refreshing to explore with the speakers its many possible definitions and faces, to challenge the notions of borders and peripheries, and reveal the more nuanced picture of migration that historical events, individuals and artefacts convey.

Closing remarks were given by Dr Spike Bucklow (Hamilton Kerr Institute), who highlighted that the conference demonstrated how much can be learnt when we cross disciplinary boundaries and hear from colleagues around the world working in different fields of conservation, technical art history, as well as history and art history, science and archaeology.


Katharine Waldron – 1st year Post Graduate Intern at the Hamilton Kerr Institute

About the Author

After completing a BA in History of Art at the University of Warwick, Katharine graduated from The Courtauld Institute of Art in 2018 with a Postgraduate Diploma in the Conservation of Easel Paintings. One of her projects involved the conservation and technical research of a modified 17th-century harpsichord lid, leading to her third-year dissertation project which focused on the characterisation and deterioration of historical copper green glazes. She has worked for Katherine Ara Ltd. and completed paintings conservation internships with the National Trust, the House of Lords, the National Maritime Museum, the V&A, and the RCE in the Netherlands as a Zibby Garnett scholar. Among her current projects at the HKI, Katharine is involved with research into the pigments and techniques of medieval rood screens and church polychromy in East Anglia.

To contact Katharine: