Conservation of the Weston Cast Court at the V&A

Part of the vision of Henry Cole (1808-1882), the first Director of the South Kensington Museum (as the Victoria and Albert Museum was then called) and its first curator John Charles Robinson (1824-1913), was to create a collection of casts of major international works of art and architecture. In 1873 the opening of the Architecture Courts, as the Cast Courts were originally known, provided a permanent home for the collection. Casts and electrotypes have been displayed in there ever since. In November 2014 The Weston Cast Court (gallery 46b) re-opened after renovation of the building and conservation of the casts. The project allowed closer inspection of the objects than had been possible for many years and has resulted in a richer understanding of the collection.

By the middle of the nineteenth century the tradition of creating copies of great works of art, not least classical sculptures, for royal and aristocratic collections had existed for over 300 years. In the late 1830s, plaster casts had been amassed for the instruction of students at the Government School of Design, which was the forerunner of the South Kensington Museum. Political aspiration to transform training in art and design in order to produce goods that would compete more successfully in foreign markets, was combined with the Museum’s remit to inform the general public: plaster casts and electrotypes were viewed as ideal material for contributing to a comprehensive display. Paramount for the development of students and artists, the Courts eventually contained a history of European art with some of the most celebrated examples of post-classical art and architecture included in plaster and electrotype form, available equally for the non-travelling public to see. During the 1860s the selection of works of art to be copied became more focused: Robinson travelled Europe extensively, commissioning work either from locals or sending castmakers to site, while Henry Cole initiated an exchange scheme whereby museums across Europe would exchange casts of monuments and sculptures held within their collections – in 1867, The International Convention was signed by the 15 crowned princes of Europe. This gave rise to a collection of increasing diversity and scale, revealing the taste and aesthetics of their time. The need for specific galleries to house them became more urgent: Since 1857, the Museum had displayed the cast of Michelangelo’s David, a gift to Queen Victoria from Duke of Tuscany; in 1862 over 2,000 casts of woodcarvings that had been used as models for the craftsmen working on the building of the Palace of Westminster were transferred to the Museum; and the acquisition of casts of other large scale works, such as Trajan’s column over thirty-five metres high which was bought in 1864 at great cost, and built in two halves, and the eighteen metre-wide Pórtico de la Gloria from Santiago de Compostela in Spain, commissioned in 1866, dictated the final size of the Architecture Courts that were built in 1873.

Two thirds of the objects now on display in the Cast Courts are from the nineteenth century. The collecting of casts gradually slowed, with the collection being supplemented by gifts such as the 1916 transfer of architectural details from Royal Architectural Museum of the Architectural Association, rather than by commissioned works. By the 1920s, the value of casts had begun to be questioned, with the last major addition to the collection being 23 casts of monuments in 1938 from the Crystal Palace after it had been gutted by fire. This history has resulted in a collection of extraordinarily wide coverage in contrast to most other nineteenth century collections in Britain and abroad which were based around local examples. 

The Cast Courts are comprised of two large galleries with a wide corridor running between. The Architecture Courts were originally conceived to house both original objects and reproductions in a variety of media – as well as casts and electrotypes, architectural models, paper mosaics, brass rubbings and watercolours of buildings and stained glass could all be found there – the space provided an extensive contrast of materials, cultures, and eras. By the early twentieth century however, original objects had been moved to other parts of the Museum or even to other Collections and the paper works, models and other materials had also been removed, leaving only reproductions in the form of plaster casts and electrotypes which have been displayed there ever since. The East court, the Weston Cast Court, presents casts of Italian architectural monuments and sculpture, while the West court houses casts of objects of Northern European and Spanish origin.

The recent renovation of the Italian court was carried out during a four-year period, and included the restoration of the roof and the floor, as well as the redecoration of the walls in the original colour scheme. The whole gallery was eventually scaffolded out to enable the replacement of the roof. This provided a working platform for the higher parts of objects. Many of the casts are only accessible from a scaffold, so the project offered us the unique opportunity of a close up view of the working methods of both the original sculptors and of the cast-makers. What looks from the ground to be extraordinarily deep carving in the original, for example in the Pisano pulpit, is exposed at close quarters to be cleverly understood viewing angles, with much less stone taken away than expected, revealing the sculptor’s economy of approach. We were also able to analyse how the casting was undertaken: numerous moulds would have been made and the cast pieces built together in situ in the galleries. In some cases part numbers to help with the installation sequence are visible, in other places we saw tool marks that were evidence of post-installation adjustment. With over two hundred casts – ranging in scale from the doorway of the Church of San Petronio in Bologna, approximately 14 metres high and originally carved by Jacopo della Quercia, to the bust of a child, 35 centimetres tall, originally made by Andrea della Robbia – the challenge of the conservation project was to balance the condition, quantity and complexity of the objects to be treated with the level of intervention and the time available.

The majority of the objects have always been on open display rather than in cases, and were thus exposed to pollution caused both by early heating and lighting methods within the Museum and by the general quality of London air. Humidity has also had an impact on the ageing material. Over the years, the casts and electrotypes have been cared for in various ways according to the approaches of the day. This has ranged from complete dismantling and re-location, partial or complete coating with paint or resins, to a variety of cleaning methods with varying degrees of success, the last major renovation having taken place in 1981. The records of previous treatments were scant and records of the makers and their exact processes were somewhat scattered. The recent project has allowed the gradual construction of a bigger picture of both aspects of the collection through close visual observation of the objects, the effects of conservation intervention through limited sampling and analysis and through the gathering of written source materials. The collection of this material is by no means complete, and the eventual conservation of the West court will no doubt bring further insight.

There are over 39 formatori, or cast-makers, represented in the collection and in reading literature on casting in plaster we have found at least 84 traditional recipes for the coatings on the surfaces and additives to the plaster. Some of the makers have been forgotten, others such as Franchi, Brucciani (both working in London) and Lelli (based in Florence), are well-known in relation to the Museum or plaster casting in the nineteenth century, while the names of yet others such as Pierotti (Milan and Birmingham) crop up unexpectedly in relation to other casting processes. All will have had their own methods and recipes for creating casts and achieving the desired finish, resulting in an unknown quantity of combinations of materials. A key issue for the formatori was how to make the cast durable. Recipes for coatings suggest among other materials: animal glue, linseed oil, milk, waxes, tree resins, pigmented paint. They were used alone, in successive layers or in mixtures. These materials have in many cases effectively protected the surfaces of the plaster for many years but have slowly broken down, yellowing and becoming eroded, resulting in patchy and now absorbent surfaces. As previously mentioned, this has resulted in some cases in later applications of protective coatings or the concealment of dirt and disfigurement by paint. 

Although the project spanned several years, the sheer area to be covered influenced our approach. Conservation treatment focused on structural stability and the removal of surface dirt; removal of layers of later coatings and paint was not part of our remit. The nature of plaster is a more complex than may be assumed at a glance – the scale of some of the objects is so great it is hard to imagine they may be fragile. It is a porous, brittle material that absorbs moisture and dust particles. If not sealed, it will alter in appearance dramatically over time and remains susceptible to erosion. The removal of dirt from the casts on open display is of particular importance because over the years dirt has contributed to the degradation of the surfaces. Before cleaning, small tests were carried out to select the appropriate method. It is not always the aim to remove the last spec of dirt – Often the dirt has become ingrained in the pores of the plaster, trying to remove that can cause damage to the surface.

For the most part, unsealed casts have been displayed under glass and therefore show the materiality of plaster at their best. We had the additional aim of revealing the material quality of the coated plasters in order to help clarify the collection to visitors unfamiliar with casting. Despite the coated plasters often having a darkened coating, this layer can become clearer through cleaning, revealing the material of plaster beneath.

Conservation started with the assessment of the condition of the casts: In general there were a limited number of casts displaying signs of serious structural issues, degradation was more evident in the form of cracking and shrinking coatings and paint layers and discoloured and eroded sealants with exposed areas of plaster having darkened considerably due to the absorption of dirt. Structural issues were often related to the method of construction. This could be installation-related, for example the cast of a window from the Certosa of Pavia (Repro.1867-39), cast by Pietro Pierotti, then based in Milan) has a large wooden substructure that clearly began to shrink soon after being built, causing cracks and distortions in the plaster. In other cases, it was related to the actual method of casting, for example Desachy’s cast of Michelangelo’s Moses (Repro.1858-278). Desachy, a formatore based in Paris, patented a technique in 1856 that allowed him to create large scale casts with extremely thin walls by the addition of scrim and timber supports, which resulted in super-lightweight but rather delicate structures. The lower half of Desachy’s cast of Michelangelo’s Moses was cast in two halves, at an overall height of almost 2.5m high. The image shows the thin structure that Desachy was able to achieve even on casts of this scale, which in total only weighs thirty-five kilogrammes. At the left edge of the crossbar that supports the top of this half, carbon fibre webbing has been added to support a broken area of plaster. This is a very lightweight material that now provides extra strength to the load bearing area. The black layer around the top edge of the joint line has been added as a softener for when the top half is added, protecting both sides of the joint.

The selection of treatments was based on a number of criteria including, first and foremost, the fact that plaster is easily softened and partially dissolved by water. Whether the surface coating was in need of consolidation as well as cleaning had an impact, and the extent to which a coating had been lost. We had very little hard information about the varied cross-combinations of the surface coatings, and have gradually developed our understanding of the structures through a variety of means.

While individual objects required close focus, we had also to bear in mind the overall context of this collection being displayed as a whole. Conversely, despite the collection having been in the same place all this time, the individual casts have been subjected to a diverse history of treatments. Collaborations with the V&A’s Science section, and with students, allowed us to gain insight to the materials of the coatings and to the numbers of layers through the use of analytical techniques such as Raman spectroscopy, FTIR (Fourier Transform Infrared Spectroscopy) and XRF (X-ray fluorescence). Further optical methods such as magnification under ultraviolet light were also used.

The treatments were often a balance between cleaning and consolidation being carried out alongside each other and cleaning could involve a number of different techniques: Our desire to avoid the use of water due to its effect on plaster was key in many cases to the selection of processes used.

While the cleaning of the casts has had an amazing impact on the aesthetic appearance of the objects which, combined with the newly decorated walls and re-glazed roof, has resulted in an uplifted space, the project has reiterated how important the removal of dirt is to the long-term preservation of the casts. The opportunity to get close to, and to undertake close examination of these objects that were previously difficult to access has allowed us to ensure their on-going stability.

Main image: In some cases, as with this figure of the Virgin and Child, original by Giovanni Pisano, combinations of poultice followed by small sponges were used. Conservators adapted the approach to each object as it progressed, according to the varying surfaces and conditions found (photo: © Johanna Puisto)

Aurora Corio