Scanning at Lincoln Cathedral

On 29th to 31st July, we visited Lincoln cathedral to laser scan the interior. The cathedral is something of a magnet for vault enthusiasts, featuring a magnificent range of mainly thirteenth-century examples which were hugely influential throughout Britain – we’ve already scanned some of their offspring at Chester and Ely.

Most famous is the so-called ‘crazy vault’ over St Hugh’s choir, one of the earliest surviving high vaults in the cathedral. There is evidence that the Romanesque cathedral had vaults, specifically in the nave, but we don’t know what they looked like. An eastwards extension of the cathedral, begun in 1193/4 under Bishop Hugh of Avalon (1135-1200), canonised St Hugh of Lincoln in 1220. As part of this project, the new presbytery was vaulted with a design involving an additional rib in an asymmetrical arrangement. This, along with other peculiarities of design and a name, Geoffrey of Noyers, described as ‘constructor of the noble fabric’ in the Greater Life of St Hugh, encouraged Robert Willis to identify the designer as ‘a mad Frenchman’ in a lecture given to the Archaeological Institute in 1848. At a time when Lincoln was venerated as a gem of Early English architecture, this comment was considered heretical, both by Anglophiles and by the French: having been invited to comment on the issue, French architect Viollet-le-Duc pronounced that the architect could not have been French (whose architecture he characterised as wholly rational) but might possibly have come from Normandy. In fact, whatever his ethnicity, Geoffrey was probably unlikely to have been the designer but was probably a clerical administrator.

Although Willis never published his lecture, which is now known only from contemporary journalists’ reports, the ‘mad Frenchman’ epithet entered the historiography, ‘mad’ being transformed along the way into ‘crazy’ and being applied to the vaults as opposed to their designer. A famous article by Paul Frankl cemented this usage and framed the terms of a debate which has continued to the present day.

So what is so ‘crazy’ about the vaults over St Hugh’s choir? Before this, rib vaults were designed either in a quadripartite (divided by diagonal ribs into four parts) or a sexpartite (divided by diagonals and with an additional transverse rib to create six parts) form. We have already scanned quadripartite vaults at Westminster Abbey and there are sexpartite vaults in the transepts of Lincoln cathedral. Both quadripartite and sexpartite vaults have a single central boss per bay of vaulting, marking the junction of the diagonal ribs. As in the transepts and nave at Westminster Abbey, English designers started to use ‘ridge ribs’ to join the bosses longitudinally. Frankl suggested the earliest example of a ridge rib was at the abbey of Montivilliers in Normandy, where the Romanesque church has transepts covered with a form of sexpartite vault. In a number of Norman or Norman-influenced churches, what have been termed ‘semi-sexpartite’ vaults were constructed – these are basically a single quadripartite vaults over two bays, the division between the two bays being marked by a ‘diaphragm arch’. The plan therefore resembles that of a sexpartite vault but the transverse rib which intersects with the diagonals at the centre of the vault bay carries a wall rather than a three-dimensional vault conoid. This type of vault can be seen in the nave of La Trinité, Caen. What we see at Montivilliers is this type of vault turned by 90 degrees, so that the diaphragm arch springs from the end wall of the transept. Once the arch reaches its apex it cannot descend, as if it did, its springing point would be mid-air in the transept. Instead it is therefore continued horizontally to meet the apex of the next transverse arch and then the crossing arch, thus forming a ridge rib. This experiment had no immediate progeny. Other early ridge ribs have been claimed for the Priory of St Mary at Airaines, where they exist alongside diagonal ribs but have a different profile, suggesting a subordinate status and, in a more typical form, in the church at Luchueux. Both these churches are in the Departement of the Somme in northern France. In England, we find early ridge ribs in the north transept chapels of Ripon Minster (probably 1170s), a building which can be related both to local Cistercian architecture and its French sources and to the great cathedral Archbishop Roger was erecting at York (now rebuilt, but elements survive in the crypt). Ridge ribs also flourished in Angevin and Poitevin architecture and were used in the similarly domical high vaults of Münster cathedral in Germany. In all cases, their aesthetic effect is rather different, so even if they do share a common ancestor, they were readily assimilated into a varied range of regional styles.

At Lincoln, St Hugh’s choir has a ridge rib which runs east-west, whose directionality was originally emphasised by painted decoration. Instead of the typical single central boss per vault bay, however, here there are two bosses. This makes the vault ‘eccentric’ (as it was described by John Bilson), meaning that it has no defined central point. Instead of converging on a central boss, the diagonals of the south side of the building converge on the more easterly boss and those on the north side converge on the more westerly. An additional rib from the other side also meets the boss, making each boss mark the conjunction of three ribs in addition to the ridge rib. This additional rib does not mark a change in plane as ribs had previously done and has been described as the first ‘tierceron’, a medieval word usually translated as meaning ‘third rib’. It is as though the diagonal extending from the north-east to the south-west corner of the bay has been split and stretched in two directions along the ridge rib. This sets up an asymmetric, sawtooth rhythm to the vault, further emphasising its longitudinality. Nothing like this had been seen previously in Gothic architecture and, as its form was not replicated elsewhere, it may not have met with contemporary approval. The great transepts at Lincoln reverted to sexpartite vaults and the nave has the first tierceron star vault.

The patterns can also be seen as being formed from pairs of ‘tri-radials’, arrangements of three ribs converging on a single boss. Frankl, a German scholar, was certainly aware that both the use of tri-radials and the asymmetric quality of Lincoln’s vault would form important elements of early fourteenth-century German and Swabian architecture, developed further in the later fourteenth century by Peter Parler at Prague cathedral and forming a key feature of late Gothic. He thus described Lincoln as a proto-late Gothic building, disrupting all standard stylistic chronologies. Whether, and how, the vaults of Lincoln might have influenced Continental Gothic became a topic of much debate – we look forward to the relevant Continental vaults being scanned so that their three-dimensional geometries can be compared with what we find in England.

There are many other current debates about Lincoln, relating to original design intentions, chronologies and extent of repairs after the collapse of the crossing tower in 1237 or 1239. We look forward to seeing what our data can add to these discussions and, indeed, whether it can offer new ways of looking at a building which has puzzled and delighted generations of scholars.

IJoAC Article

Our article investigating the use of digital generative design tools to assist with analysis of Exeter cathedral has now been published in  the International Journal of Architectural Computing.  This article can be viewed here – please contact us for further information. Abstract below:

Medieval masons relied on a ruler and compass to generate designs of increasing complexity in both two and three dimensions. They understood that arcs and lines could be used for proportioning, working with halves, thirds, fifths and so on, rather than specific dimensions. Geometric rules enabled them to create vaulted bays, high up in church and cathedral interiors. In recent years, the influence of digital generative design tools can be seen in our built environment. We will explore generative design to reverse engineer and better understand the design and computational processes that the medieval masons might have employed at our case study site of Exeter Cathedral, England. Our focus is on a run of bays along the nave, which at first appear consistent in their design, yet in reality are subtly different. We will investigate the capacity for changes in the generative process while preserving the overall medieval design concept.

Webb, N., & Buchanan, A. (2019). ‘Digitally aided analysis of medieval vaults in an English cathedral, using generative design tools’, International Journal of Architectural Computing, July 2019.

Scanning at Norwich Cathedral

This week we have been scanning at Norwich cathedral. This is the biggest site we’ve tackled to date – the whole Norman cathedral was covered with lierne vaults in the 15th century and there is also a tierceron vaulted cloister and a 14th-century lierne vault in the so-called Ethelbert Gate into the cathedral precinct.

Like other sites we have previously scanned, including Gloucester cathedral and Tewkesbury abbey, Norwich cathedral remains largely a Romanesque building, originally built as a visible symbol of the Norman Conquest of 1066. The elevations display the massive piers and round-headed arches typical of Romanesque architecture. Although undoubtedly impressive, this style would have looked very old-fashioned by the 14th century, so when the central spire blew down in 1362, damaging the east end of the building, the monks might have seen this as a good opportunity to update their church. The presbytery clerestory (top storey of windows) was rebuilt with Perpendicular tracery and, in the fifteenth century, the whole building was vaulted. The Norman walls had not been intended to carry stone vaults, so we will be interested to explore what effects these might have had on the existing fabric. Moreover, in reverse, the existing bay dimensions would have placed specific requirements on the 15th-century designers, inevitably affecting their artistic freedom.

We selected Norwich as one of our case studies for a number of reasons. Firstly, Professor Robert Willis noted that the cloister vaults showed a number of different 3D forms, despite all following the same 2D plan. Such situations – which we knew existed at Wells cathedral and have also found at Exeter – provide very interesting data for our analysis, revealing the sophistication of medieval design processes. We are therefore very much looking forward to interrogating our scan data once it has been processed. It may also provide further clues for understanding the sequencing of the cloister – the dates at which the different parts were erected – which has long been an interesting puzzle for archaeologists.

In addition, Norwich will provide an interesting comparison with Ely cathedral, as we know from documentary evidence that the same named masons worked on both sites. Members of the Ramsey family worked at Ely and Norwich in the early fourteenth century (as well as at St Stephen’s Chapel in the Palace of Westminster, whose surviving undercroft we have also scanned). Our data may help to identify whether the Ramseys and their teams used the same design methods at different sites and whether their approach was different from our other West Country vaults.

Finally, it has been argued by Frank Woodman that the vault of the Ely Lady Chapel is not 14th-century, as had always been assumed, but dates from the 15th century. He used the high vault at Norwich as a comparison for dating purposes, therefore it will be interesting to see whether laser scan data can be used to support or disprove his theory. The Norwich cathedral lierne vaults are the latest in date that we have scanned and we will be looking to see whether methods had remained constant from the 14th century or whether familiarity with the techniques had enabled improvements.

We are very grateful to all the staff at the cathedral, especially Roland Harris, the Cathedral Archaeologist, for facilitating our visit and making us feel welcome in this beautiful building.

Fire at Notre-Dame

We were shocked and saddened at the scenes from Paris as Notre-Dame Cathedral blazed in the night. Today’s news that the structure of the building seems to be safe has come as a great relief, given its importance both as a symbol and as a monument of Gothic architecture.

The word-famous cathedral was started in around 1160 and the west front dates from the early years of the thirteenth century. Later in that century, the upper storeys were remodelled to introduce a larger clerestory with traceried windows and the transept facades, with their celebrated rose windows, were added. As the mother church of Paris, the building has undergone many alterations and additions over its history, most significantly at the Revolution, when religious images were attacked, and in the nineteenth century, when architect Viollet-le-Duc undertook a major restoration, including the rebuilding of the wooden spire whose dramatic fall became one of the defining moments of the inferno.

Thoughts are already turning to the possibility of reconstruction, to which President Macron has stated his commitment and many millions of euros have been pledged from around the world. This is where research such as ours can be particularly valuable. Thanks to years of surveying and a recent laser survey by the late Professor Andrew Tallon, Notre-Dame is probably one of the best documented medieval buildings in the world. The level of detail provided by a laser scan, consisting of millions of digital points recorded in space to create an exact 3-D digital model, could enable a reconstruction to produce a stone-by-stone replica of a destroyed building. That is not to say that laser scanning would provide all the answers: scans can only record what is visible and cannot identify what is going on under the skin of the building. In particular, wooden roofs of the kind that has been destroyed at Notre-Dame are particularly difficult to document by digital means. Nevertheless, laser scan data would make it relatively easy to interrogate the geometries of the parts of the vaulting that have been lost, in order to accurately recreate their three-dimensional form. The geometries used would thus be based on an understanding of the design methods originally used by the medieval masons. There is a wealth of expertise that the reconstruction team could draw upon to assist in this work, with researchers in Spain, Germany and the United States (as well as us in the UK) all using digital techniques for documentation, interrogation and reconstruction purposes.

Paradoxically, it has often been the case that disasters have helped to enhance our understanding of buildings. The nineteenth-century architectural writer, Robert Willis, who has inspired our research, explored the debris surviving after the collapse of one of the western towers of Canterbury Cathedral and found a stone from the fourteenth-century vault still inscribed with the setting-out lines used by the masons when cutting the vault ribs. He used this as evidence for understanding how their designs were projected into three dimensions. Viollet-le-Duc used his experience of very thoroughgoing restorations to draw conclusions about medieval vaulting techniques, including at Notre-Dame. Some of his theories about the structural behaviour of vaults were challenged by the destruction of some of the northern French cathedrals during the First World War: at times the ribs collapsed, leaving the webbing, supposedly supported by the ribs, still standing without them. It may be hoped that the damages at Notre-Dame might be equally enlightening for further research on early Gothic vaulting, which can then inform the rebuilding.

Victor Hugo, whose 1831 novel Notre-Dame de Paris (more famous in English as The Hunchback of Notre-Dame) called for the restoration of the cathedral, spoke of three agents of change: time, revolution and fashion. To this should be added disaster. He understood all works of architecture as social products, the sediments of ages – as he put it ‘Time is the architect; the nation is the mason’. The future reconstruction of Notre-Dame should be seen in this light. It cannot return Notre-Dame to how it was before the fire, still less to any ‘original’ medieval state. Indeed, even if timber on an adequate scale were available it could be questioned whether there is value in replicating a less visible part of the building whose significance lay in the original timber and medieval carpentry techniques. Nevertheless the reconstruction work of the twenty-first century, which will doubtless use both traditional skills and cutting-edge technologies, will form the latest chapter in the biography of this beautiful building.

Image credit: Antoninnnnn

In memoriam – Andrew Tallon

We were very saddened to learn of the death in November last year of Professor Andrew Tallon, whose obituary was published on the Society of Architectural Historians’ website.

Although we did not have the privilege of meeting Prof. Tallon, we had corresponded with him about our shared interest in digital methods in relation to medieval architecture. Ongoing medical treatment meant that, although delighted to have been asked, he was unable to accept our invitation to speak at our 2016 conference. We had hoped to invite him again to speak at our next symposium, where he will now be a sad absence.

Prof. Tallon was one of the first medieval architectural historians to identify the potential of laser scanning to the study of medieval architecture and the value of digital tools both for research and outreach purposes. His contribution to the Mapping Gothic France project has helped to make it a hugely valuable resource and he explored the possibilities offered by film and exhibitions to share his knowledge of French Gothic.

Of particular significance to our own research, Prof Tallon used the data gathered from laser scanning to look at medieval design methods, providing secure data to overcome the obstacles faced by earlier researchers. In his article ‘Divining Proportions in the Digital Age’ in Architectural Histories 2:1 (2014), he discussed the technique of laser scanning in relation to analysis of the planning of the cathedral of Notre-Dame de Paris. Showing a generosity we understand to have been typical of his character, he also shared his data with Robert Bork, who used it in his article ‘The Geometry of Bourges Cathedral’, Architectural Histories, 2.1 (2014). Equally importantly, Prof Tallon used data derived from laser scanning to inform a method he described as ‘spatial archaeology’, the close observation of building deformation. In articles such as ‘Rethinking Medieval Structure’, in New Approaches to Medieval Architecture, ed. R. Bork, W.W. Clark and A. McGehee (Farnham and Burlington VT: Ashgate, 2011), pp.209-17, he used this approach to demonstrate convincingly that flying buttresses had been a feature of French Gothic architecture from the outset, rather than being added to early Gothic buildings at a later stage. Although the English Gothic buildings on which we are focussing are far less adventurous in engineering terms than French cathedrals, we have used his methods to argue that apparent anomalies within our data are unlikely to result from settlement, as the walls we have so far analysed are similarly vertical. Nor was Prof Tallon’s research confined to questions of construction: he was equally interested both in historiography and symbolism. His research on the supposed ‘refinements’ to Gothic proposed in the early twentieth century by William Goodyear (1846-1923), published as ‘An Architecture of Perfection’ in the JSAH, 72:4 (2013), pp.530-54 showed that not only were such displacements not intended by the original builders but also went against their understanding of the importance of being ‘upright’ in both structural and moral terms.

As Prof Tallon had undertaken a major programme of scanning at Bourges Cathedral, we had been looking forward to discussing with him any findings on the three-dimensionally curved ribs of the ambulatory, which seem to be unique for their date. It is a matter of great regret to us that his untimely death cut short an ongoing conversation and has deprived our field of one of its great innovators. He will be very sorely missed.

Scanning at Westminster Abbey and the crypt of St Stephen’s Chapel

In January 2019, we travelled to London to undertake a digital survey of the medieval vaults of Westminster Abbey and the Victorian reconstructed vaults of the undercroft of the destroyed St Stephen’s Chapel beneath the Palace of Westminster using funding from the AHRC.

Westminster Abbey, perhaps the best known church in the UK, offers a number of valuable opportunities to the project. Whilst most of the hundreds of thousands of visitors each year pay homage to Britain’s illustrious dead buried there, architectural historians continue to argue over whether the nation’s mausoleum owes more to France than to England. Our research will enable us to compare Westminster’s vaulting with other sites both in the UK and in France to explore the ‘Frenchness’ of its design. Furthermore, the chapter house and cloister vaults have previously been identified as having unusual 3D geometries, so we will use our digital data to investigate this. As a royal project, Westminster is also unusually well documented in the records of the King’s Works, throwing further light on the building sequence, the identity of the designers and details of construction methods. From such records, we know that the medieval masons plotted their designs on a full size ‘tracing floor’, from which moulds were cut for the individual blocks of stone and the wooden formwork by which the ribs were supported during construction.

St Mary Undercroft, formerly the crypt of St Stephen’s Chapel in the Palace of Westminster and now the place of worship for the Houses of Parliament, is another well-documented royal work, started by Edward I. Its vaults take an innovatory ‘lierne’ form, with extra decorative ribs which have been claimed as the earliest liernes in England. Although now largely a Victorian reconstruction following the great fire of 1837 which destroyed most of the medieval palace, measurements were taken from the medieval vaults prior to demolition. Our digital survey will be used to compare the measurements of the demolished medieval design with the current Victorian reconstruction and possibly identify elements of original medieval fabric lurking beneath the Byzantine-style paintwork.

The two surveys add to a growing list of case study buildings that will be individually analysed, as well as offering comparisons between sites. We are currently making good progress with analysis at Exeter, Ely and Wells cathedrals, and will begin investigations using the Westminster Abbey and St Stephen’s Chapel data later this year.

Join our team!

We are seeking to appoint a Postdoctoral Research Associate and a Research Technician on a fixed term contract to be part of our exciting AHRC funded project titled ‘Tracing the past: analysing the design and construction of English medieval vaults using digital techniques.’ Further details of the posts can be found via the links below:

Postdoctoral Research Associate (18 months full-time)
https://www.jobs.ac.uk/job/BNR596/postdoctoral-research-associate-grade-7

Research Technician (6 months full-time or 12 months part-time)
https://www.jobs.ac.uk/job/BNR738/research-technician-grade-6-full-or-part-time

For queries, please email Dr Nick Webb – njwebb@liverpool.ac.uk

Digital Heritage 2018 Presentation

In October we attended Digital Heritage 2018 in San Francisco. Here we presented our initial investigations into the vault design of the Lady Chapel at Ely Cathedral, as well as outlining our digital methodology which enables the research to be carried out. The next stage of this case study is to focus on dissemination as well as identifying possible trends with other vaults at Ely, as well as comparisons with sites locally and nationally.

Whilst at the conference we saw several intriguing presentations, such as Jongwook Lee’s framework for managing risk in Korean wooden heritage buildings using Heritage Building Information Modelling and Virtual Reality, Gabriele Guidi’s reconstruction of the hidden Roman Circus in Milan, as well as excellent keynotes from Google and Artec3D.

6ICCH Presentation

 

In July we attended the 6th International Congress on Construction History, hosted in Brussels, Belgium. The conference included participants with a wide range of interests in construction history and there was a strong showing of researchers investigating vault design and construction. This included colleagues from Spain and Germany, such as David Wendland and Marie Jose Ventas Sierra’s  talk on the Hall of Arms vault in Albrechtsburg Meissen as well as Rocio Maira Vidal who discussed the abandonment of sexpartite vaults across Europe, including Lincoln Cathedral in England. It was a delight to meet Jacques Heyman, who wrote ‘The Stone Skeleton’, and gave a fascinating talk on the change of level in the fan vaults at Kings College, Cambridge.

At the congress we shared our initial investigations of the nave and choir vaults at Exeter cathedral, which we surveyed in 2016. We suggest that all the high vaults were laid out in two dimensions using a geometrical figure called the ‘starcut’, allowing the same proportions to be maintained throughout, despite different bay dimensions. The three-dimensional geometry of the vaults, however, presents significant variation between bays. These appear to correspond with the construction sequences proposed by previous scholarship. Nevertheless, the nature of the variations does not correspond fully with previous interpretations. We propose that two-centred arcs were found at Exeter earlier than generally recognised and in a different pattern of distribution than previously suggested.

More information on 6ICCH can be found here.

English Medieval Vaults