Report on the assessment and treatment of the reredos stone from the chantry chapel of Bishop John de Sheppey, c.1340, by Carla Learoyd.

Extracts from ‘Engaged Capitals from Rochester Cathedral; Condition and Treatment Report, Carla Learoyd, 2022/23. Full report available here.

It was one of several fragments discovered during excavations of a blocked-up opening by architect Lewis Nockall Cottingham in 1825, while restoration works were being conducted

Discovered amongst the rubble was the brightly polychromed effigy of Bishop John de Sheppey (c1300-1360). It was found in a semi- upright position, alongside several fragments thought to be part of a reredos screen that would have once adorned the chantry chapel belonging to Bishop de Sheppey himself. It is thought that the effigy and other fragments could have been hidden in a hurry to avoid being destroyed or defaced by iconoclasts during the time of The Reformation, although this is not known for sure. So far it has not been confirmed that the fragments do relate to the effigy but since their discovery, they have remained at the cathedral, most recently stored in the lapidarium.

The fragment consists of two ornately carved capitals engaged by a central lantern section, displaying historic polychromy and gilding. Both capitals spring from a black painted base divided into three sections by gilded bands. The middle of these sections displays a quatrefoil cut out with a gilded edge and a red painted recess.

Base of proper left capital.

Carved acanthus style foliate mouldings spring from the base of both capitals, each topped with a polygonal abacus, divided into polychromed and gilded bands.

Left: foliate detail to Proper Left capital.
Right: Foliate detail to Proper Right capital.

Image showing rounded nodules to top edge of Proper Right capital.

The central lantern section displays two lancet shaped niches, both displaying evidence of polychromy.

Lancet shaped niches to central section.

A thick vine trails across the surface, intersecting the central section, adorned with bunches of grapes and undulating vine leaves displaying spectacular undercutting that highlights the intricate detail.

Left: Vine with carved bunches of grapes. Right: Close up of vine leaf.

Close up of undercutting to vine leaf on Proper Left side.

Five round holes can be seen to the centre of the fragment although it is not clear what their function is.

Close up of one hole to central area of fragment.

Extensive tool marking is visible to the rear, top and base of the fragment.

Visible tool marking to the top of the proper left capital.

The top surface of all three sections exhibits as flat, aside from a metal loop, set into a timber insert, positioned into the top of the central lantern section.

Timber insert topped with metal loop, to top of central section.

The Origins of the Chantry Chapel

The tradition of founding chantry chapels began in the 13th Century across Europe, but many were abolished during the English Reformation. It would usually be a dedicated space within a church, to allow the congregation to pray and sing masses for its founder after his death in the hope that his soul would go to heaven (Cook, 1963).

An effigy of the founder would usually be displayed on a stone tomb chest. The location of the tomb within a cathedral was an indication of their standing within the congregation and local community. A common design of the chantry chapel was a stone-cage type, enclosed by screens and topped by magnificent canopies crowned with pinnacles that would be adorned with crockets. A crocket is a small medieval style ornament that would project outwards from a feature such as a pinnacle or a capital, usually in foliate form. Such details were commonly referred to as micro-architecture.

Sketch of an example of a stone-cage chantry chapel belonging to Cardinal Henry Beaufort, Bishop of Winchester (1404-1447) in Winchester Cathedral Top right: Close up sketch of pinnacles Bottom right: Close up sketch of a crocket on the pinnacle. (Missouri.edu, 2022).

Reredos: “A screen, which may be carved or ornamented, behind an altar”. (Beatty et al, 1944)

If this fragment is thought to be part of a reredos, it is likely that the chantry chapel from which it came was of the stone-cage type which allowed such a screen to be positioned behind the altar, and the effigy would be positioned facing it, allowing it a glimpse of heaven. A reredos would often be highly ornamented, depicting images of religious figures, or containing niches that would support statues.

Historical changes:

Observation of the bottom elevation revealed a later repair had taken place to the front edge of the central section. The repair seems to have been carried out in a sympathetic manner, possibly using the same section that became detached as the substrate on both sections exhibits a similar surface appearance (Fig.19) The fill material that has been used is dark brown in colour and under X200 magnification appears to be brittle (fig.20).

Left: View of replacement to top edge.
Top right (a & b): X200 magnification of both sections.
Bottom right: X200 magnification of fill material.

Historical context

John de Sheppey was consecrated as Bishop of Rochester in 1353 at St. Mary Overy, Southwark. Following earlier studies in Paris and at Oxford, he became a reputed preacher, writing many sermons that became volumised.

He founded a chantry chapel at Rochester Cathedral in 1360 at the altar of St. John the Baptist in the North Choir Transept. After his death a daily mass was to be said for the souls of the King, the Bishop, and others and on the obit-day the sum of two marks was to be given to the monks for pittances, which were food and drink:

‘And because the number of monks varied after such distribution, the residue shall be used for other useful work within the body of the church to the preservation and repair thereof’ (Cook, 1963).

The effigy of Bishop de Sheppey can be viewed at Rochester Cathedral, although its current situation is not thought to be its original location.

The effigy of Bishop John de Sheppey as he is currently displayed in the Eastern Aisle of the North Quire Transept at Rochester Cathedral.

Discovery of the fragments:

Much of the original literature, imagery and correspondence regarding the fragments and the effigy has survived, documented in the cathedral archives, providing an authentic account of the programme of events that led the fragments to where they are now. 14 Cottingham produced beautiful illustrations of how he imagined the fragments would have been pieced together before the reredos was disbanded (figs.22 & 23)

Sketch from the time of the discovery of the fragments.

Illustrations from a publication by Cottingham in 1825 showing a reconstruction of the reredos.

One other fragment discovered by Cottingham that relates to the acanthus section, was a reredos finial fragment (object no.42 at Rochester Cathedral), depicting Moses carrying a tablet of the ten commandments (figs.24 & 25). According to Cottingham’s illustrations, this fragment should sit on the top of the central section of the reredos fragment. 3D Images on Rochester Cathedral’s website have also recreated this scenario (fig.26)

Fragment of Moses carrying The Ten Commandments, currently on display in the Cathedral crypt.

Decorated sketch of the fragment of Moses sitting on top of the central section of the acanthus reredos fragment.

Reconstruction showing the Moses fragment positioned on top of the central section of the acanthus capital fragment.

Further observations of the Moses fragment revealed details that would commonly appear on a reredos, such as the pinnacle adorned with crockets. The presence of gilding and polychromy was evident, similar in appearance to that seen on the acanthus capital fragment.

Original Structure

The fragment has been carved from one piece of stone. The visible tool markings confirm that hand carving was the method of construction (fig.45). The intricate detail of the vine, leaves and grapes has been created using the process of undercutting to remove substrate from beneath, creating three-dimensional details (figs.46 to 47)

Top view of undercutting to Proper Left bottom corner.

Surface:

Polychromy and gilding can be seen to the front elevation. Some areas of polychromy and gilding visible by eye are highlighted below (fig.48)

Nb.: The depth of colour applied to the diagram is purely for observational purposes and not indicative of the current level that remains.

Some areas of gilding and polychromy visible by eye.

Polychromy:

Polychromy on stone is the "practice of decorating architectural elements, sculpture, etc., in a variety of colours." (Harris, 1983).

Not much polychromed sculpture from the early Gothic period within medieval churches in England remains intact. Due to the action of iconoclasts during the Reformation, many pieces were smashed into fragments, sometimes used to block up the reredos from where they originally came (Boldrick et al, 2002). These fragments would often not be discovered until restoration work centuries later, mostly in a poor condition, although traces of the once spectacular gilding and paintwork would often survive. Typical pigments used would be red lead, lead white, vermillion, red lake, copper green, Verdigris, and indigo (Boldrick et al 2002).

It is thought that much of the polychromy visible on the reredos fragment is the original 14th century scheme, however, some areas could have been overpainted later, as was the case with the De Sheppey effigy. Further analysis using methods such as cross-sections or pigment dispersions, could aid in identifying the pigments and binders used, also giving a better overview of the painted and gilded scheme.

To provide an overview of some of the polychromy and gilding present, close observations were first made using a dinolite, a digital microscope that allows close images to be viewed and saved using compatible software. Following this, the same areas were observed using a portable mobile phone microscope of X200 magnification.

Close up observation of polychromy to proper left side:
A: Tip of vine leaf,
B: Centre of vine,
C: Centre of vine,
D: Vine tendril,
E: Red paint deposit to tip of quatrefoil detail,
F: Black polychromy to base.

A-B: Observed under X200, C-F: Observed using a Dino-lite X200

Close up observation of polychromy to central section
A: Black area above grapes
B: Blue/green lancet niche
C: Red niche
D: Surface of top vine leaf
E: Area of leaf showing traces of red
F: Base of vine

A – F: Observed using a Dino-lite

Observation of polychromy to proper right side:
A: Front surface of vine leaf
B: Top of vine
C: Surface of grape
D: Painted tip of quatrefoil cut-out

A-D: Observed using a Dino-lite.

Gilding

Much of the gilding has been retained although there are many areas of fading and loss. Observation by eye reveals that gilding could have been applied on top of areas of polychromy, alluding to more than one scheme. As above, analysis by cross section could provide further information. Proper left side:

Observation of gilding to proper left side using a dinolite:
A: Outer face of top edge
B: Thin gilded band to abacus
C: Centre of top vine leaf
D: Centre of bottom vine leaf

A-D observed using a Dino-lite.

Observation of the gilding to the central section using a Dino-lite: A: Top gilded band of abacus B: Area to bottom of lower vine leaf exhibiting traces of red

CONDITION

Following examination by eye it can be noted that the core of the fragment is generally stable. Much of the front surface is exhibiting extensive soiling in the form of dust and dirt that has accumulated over many years and much of the gilding and polychromed detail is exhibiting large areas of loss. Abrasions are evident on many surfaces and losses of both a recent and historic nature can be seen to some edges and to the foliate detail. It’s possible that the thinner areas of carving, such as the vine leaves, created through the process of undercutting, became more vulnerable over time, leading to some of the losses that can be seen. The following images will highlight these aspects further:

Structure

Front Elevation: The substrate is displaying historic and recent losses to many areas. Minor losses can be seen to many edges with major losses occurring to the vine leaves in the central part of the fragment and the tips of many of the foliate mouldings. Recent losses include the tip of a foliate detail to the proper right side that became detached during transportation revealing original substrate that is now vulnerable to further loss.

Close up of losses:
A: Recent loss to foliate tip,
B: Historic loss to vine leaf,
C: Historic losses to foliate.
D: Major loss to top of central section,
E: Loss of vine stalk to proper right side,
F: Loss to tip of vine leaf.

Observation of dispersions and cross sections

Following analysis of the surface using microscopy, several methods used are synonymous with those that would be used in the 15th century, the date assigned to this fragment. According to Cennino Cennini several layers of boiling hot size should be applied to the stone before application of a ground layer, to act as a sealant (Thompson, 2019, pp118). Many of the cross sections display pink staining to the bottom layer, visible after the application of the non-fluorescent stain Acid Fuschin. This indicates that proteinaceous materials such as rabbit skin glue could have been applied as a size layer onto the substrate. A ground layer can be seen on many of the cross sections, also visible on the surface of the stone as a white layer. The presence of a green materials in all the dispersions, that matches to the morphology of the green earth pigment identified on the vine leaf, points to the ground layer being tinted with the earth green pigment, applied across the whole surface of the stone, on top of the size layer. Much of the surface appears to have mordant oil layers applied beneath the pigment layers, acting as both a support for the paint and a barrier for the ground layer beneath. Staining of the gilded cross section confirmed that oil gilding has been used across the fragment. Visible polychromy appears to be a combination of lake pigments and earth pigments typical of polychromy in 15th century. The vibrant colour scheme of bright reds, greens and blues as can now be imagined, was typical of medieval schemes (Thompson, 2019 pp106). A red lake glaze has been used to highlight specific elements such as the surface of the grapes, smaller sections of the vine and on top of gilding on some parts of the vine leaves. Applying a coloured oil glaze over gilding was common in Medieval times, especially red over gold (Thompson, 2019 p66). The bright pillar box red to both quatrefoil niches was suspected to have been applied later due to the remnants visible on the gilded tips. Cross sections revealed this was indeed the case. Two layers of differing shades of red can be seen, separated by a white pigmented layer. The lower layer, possibly original, is a deeper red than the more orange/red appearance of the upper layer. The cross section of the red band displays the same stratigraphy indicating that the bands may also have been re-painted later. Continuing to look at areas of overpainting, it seems that both the niche windows (figs. 186 and 188) to the central lantern column would originally have been red, yet the niche to the proper right has been overpainted the vibrant blue that can also be seen on the bands to the capitals. Nobody can know the intentions of the artist when making this decision, but the mirroring of the bands to the top of the capitals in red and blue does add some cohesion to the scheme. Taking dispersions and cross sections from an object of historical significance always comes with some risk as these are interventive measures that physically remove original material. However, in this situation, undertaking such measures has proved to be beneficial in providing important information regarding the methods used and the colours applied on an object of great interest. It should be said that the conclusions drawn are based on the closest comparisons that could be drawn against published examples of pigment dispersions and techniques used in Medieval times.

Cleaning

Following testing and analysis, all surfaces of the stone were first dry cleaned using a combination of soft bristled brushes in conjunction with a conservation vacuum to eliminate loose debris and dust. To reduce soiling on the black background, a piece of groom stick and smoke sponge were used first, followed by saliva on a cotton wool swab stick. Various areas of the carved detail were wet cleaned using saliva on a cotton wool swab stick.

Grapes before and following cleaning.

Central lantern before and after cleaning.

Vine leaf to the proper left bottom corner before cleaning.

Central vine leaves before and following treatment.

As the gilded foliates were oil gilded, a 5% solution of Tri-ammonium citrate (TAC) was applied using a cotton wool swab stick to clean these areas (figs.204-207).

Proper left gilded foliates before and following cleaning.

Proper right gilded foliates before and following cleaning.

Once the red quatrefoil to the proper left section of the fragment had been cleaned using saliva on a cotton wool swab stick, it was noted that the surface was vulnerable with small fragments displaying movement. For this reason, the surface was consolidated using 5% Mowital B30H (PVB) in acetone as used on other areas. Following this consolidation, gentle cleaning was continued (figs.208-209).

Quatrefoil to proper left side before and following cleaning.

Quatrefoil to proper right side before cleaning.

Further work included consolidation and toning in, see the full report for further details.

After treatments photos

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Rochester Cathedral Research