The notion of the master mason has always been a touchstone for architects and builders; a mythic figure who, between the 12th and 14th centuries, created Gothic masterpieces; vast cathedrals of stone and glass, that still stand today. Think about Notre Dame de Paris, the stunningly complex tourist trap church on an island in the middle of the Seine. That building was erected over 750 years ago. And, it was built without the benefit of telephones, faxes or computers, or even paper for drawings, (yes, they had no access to paper or parchment. It was too valuable at the time and was saved for things like illuminated manuscripts instead). On top of all this, the masons who created it didn’t have measuring tapes. I know, you will say “hang on, surely the Romans used string with knots tied in it or such?”. They did. But there was no Imperial or Metric System to set a central standard for length across a region. Each master builder had to devise their own system of lengths, which becomes particularly significant when you consider the manner in which these kinds of buildings were constructed (discussed later in this piece). Now, think about what and how we build today… we produce very little that is comparable.

Until very recently, because of little available documentary evidence and, to be frank, a lack of real fieldwork by archaeologists, there was no in-depth understanding of the processes of Medieval building. A large number of assumptions were made about the methods used to design these buildings and the sequences in which they were constructed during the period. Speculation, disagreement, and leaps of faith were rife among historians; Who built them? How and in what order did they build them? How much did they cost and how were they funded? How long did it take? Surely an architect or central designer must have guided the construction? All these questions went unanswered, or were merely the subject of guesswork, until the mid 1980’s. There simply were no records of any kind available that named individuals or groups, or discussed how they went about their work during the Early and High Gothic periods. It took an unknown Australian architect, John James, and his wife Hilary, to crack the mystery of the cathedrals and the master masons.

They did this firstly through expert detection rather than typical archaeology. And secondly, they did it through sheer hard work and commitment. Between 1969 and 1974, they carried out on-site surveys to locate all the Early Gothic churches in the Paris Basin, living for much of this time in a camper van with their children. They visited each of the 3,500 churches in the area, often repeated times, to identify the 1,740 of them that had been built between 1100 and 1250. This had never been done before. Along the way they collected a vast quantity of data on all aspects of these churches, including over 40,000 photographs of every carved capital. It was only through this remarkable and forensic process were they able to decode the working methods, and even the mind-set, of the master masons, in the following years. James’s extraordinary work is better known to historians than architects these days it seems.

By literally examining and recording every course of stonework in Notre-Dame-de-Chartres (rebuilt ca. 1194 to 1230. Its West Front is shown in the elevation drawing above) James identified the work of individual masons by the marks they made on stones, to ensure they got payment, and the unique geometries and template shapes each used for setting out their own elements of the works. What James deduced was that nine contracting teams built and incrementally designed the bulk of the cathedral, ‘returning again and again in a disorderly and little supervised annual sequence for over thirty years’. Nine individual teams of approximately 300 men, with attendant quarriers, rough stone cutters, sculptors (“imagiers”) and apprentices, constructed the building in a start-stop fashion. Each group was led by one master mason who controlled this huge workshop with a team of 50 skilled stone cutters as his management team across the site. The coming and going was due to a variable funding supply and the long setting times of mortar. The large number of workers would leave the site en masse once funds ran out or while mortar was setting. They would seek work on another site during the intervening period while the church raised donations. When funding was re-established again, inevitably, they would be engaged on another project and therefore a new master builder would need to be appointed, with this new team then taking over and building on what had come before. This appears to have been an accepted practice across all Medieval churches during this era and did not inhibit achieving a unified whole in the buildings, as is evident in Chartres. The same nine roving teams appear to have contributed to nearly all the churches in the Paris Basin including works under royal patronage like Saint-Denis and la Sainte-Chapelle (in these cases where funding would have been more stable and constant the setting of mortars was the main reason for the cyclicity of the masters in charge). Crucially, there was no individual architect or constant guiding influence over the design. Each master mason (and their company of tradespeople) shows great skill in all aspects of design, engineering and construction and clearly re-designed significant parts of these buildings once they took over. The re-designing can be read in the changes in profile and templating of subtle wall geometry and in substantial formal elements like towers and structural devices. You can imagine, over a 30 year period, both styles and technology, and even the taste of the priesthood clientele, evolving, with the next mason transitioning his design into the new mode. Once the patterns were highlighted by the James’s these transitions could be easily read in the strata of the buildings. These itinerant bands of builder-architects appear to have cornered the market in cathedral building in Western Europe.

What I find most remarkable is how James was able to sketch out aspects of these masons’ personalities and their values and intentions, from examining the stones. At first I was skeptical. But you can see it when the evidence is presented. The first mason who set out the apse of Chartres is described by James as a ‘seriously philosophic man, skilled as a mason and with a considerable understanding of the Christian theology of his day’. His work can also be found at the huge Cistercian Abbey of Longpont as well as at the cathedral of Laon. This first mason began his work at Chartres in 1194, you can track the profile of his company’s masonry template; a unique signature, but it can been seen that he did not stay long on the site. The profile ends and changes within 2 years of stone courses. The second and third masons of the project were working at the site around 1196 with the first returning again in 1200 for the setting out of the south porch and the labyrinth. The evidence suggests that there was no formal procedure for passing on overall design intent from master to master, even through the client. Engineering at the time was entirely geometrical rather than theoretical / mathematical and because of this it varied greatly from master to master. They had no equivalent to Pythagoras’ theorem or bending moment and shear force calculations. They devised their own engineering rules through trial and error, geometrical inference (eg. a triangle or intersecting circles look and feel like strong shapes, “let’s try them”), and plain guesswork sometimes (stuff did fall down more than occasionally). Each successive master-builder imposed his own set of proportions and techniques on the plan without erasing his predecessors work. Remember the issue of measuring tapes and agreed lengths? Consider the difficulty of extrapolating modern-day Imperial measurements to Metric measurements. It’s tricky even with the assistance of conversion tables and calculators and does not always neatly interlock. Now picture trying to reconcile measurements for your own design with another person’s whose system is a trade secret of that building company or guild. This idiosyncrasy, and unusual deference to their predecessors, allows us to clearly distinguish and see patterns of work in this architecture, and ultimately to identify people.

The ways the master masons arranged and shaped the stones is unique to each of them. The templates they created for themselves and their teams are like fingerprints and each band of the structure that they controlled separately becomes readable. The engineering knowledge they used and refined was passed down through generations of families, gifted to favoured apprentices and pupils, or treated as a trade secret held within Guild organisations. This was arcane information which the public was barred from. This is largely the reason why we have such an incomplete understanding of their methods but also the reason we can isolate individual contributions. It is fascinating to imagine an architect setting out a building, leaving the job, and then returning 6 years later to continue the work of a number of other master architects who had progressed and modified their initial design in the intervening period; think of Frank Lloyd Wright, Le Corbusier, Neutra, Sullivan, Gaudí, Behrens, Alto, Schindler, Zaha Hadid, and Mies van der Rohe all working on the same building. The modern artistic mind-set could not accommodate such collaboration and deference (when I say “modern” I mean everything from the start of the Renaissance onward). Stylistic differences aside, this is the caliber of craftsmen we are talking about here; a very select group of artists that are sought out by the greatest institutions and patrons of the time and commissioned to carry out priceless works. To be entrusted with creating an artifact that was intended to communicate the ideology, whether it be religious or secular, of the most powerful people and groups of the time, and to set it in stone, suggests these builders held a special status. The cover image at the top of this post shows a bas-relief carved into the slab set on top of the tomb of thirteenth century master builder Hugh Libergier at Reims Cathedral. Even though from a slightly later era, the very existence of this ornate, symbol-laden, tomb and the figure it depicts supports that the master builders were likely to have been of the Burgher class, highly skilled and regarded, and clearly well rewarded (image after an illustration shown in Phillip Ball’s book Universe of Stone (2008) P140).

James believes that an initial timber model would have been made for the design with agreement of the client (as mentioned, no drawings were used for the early Medieval design and building process, only later in the period did full scale 1:1 drawings become popular to guide the carving of ornate details) but then numerous and fundamental changes were made through construction by each master depending on budget and changing tastes. James states;

“The general layout was therefore determined before erection began, but the precise sizes and details were not finalized, but left to those individuals who happened to be on site. Thus we may describe Medieval building as an ever-changing dynamic processes over time. It meant that the authority of whichever master was in charge was so highly regarded he could modify or mutilate whatever had been started by his predecessors. This applied only to what had not yet been placed as there is evidence to suggest that once erected the [prior] work could not be altered. This emphasises the enormous and often costly authority given to the master to run the works and handle the detailing to his own discretion” .

At the time there was no formal method for sharing experience or cautioning against errors in construction either (no European or International codes). As James says; ‘in these circumstances clients would have had to rely heavily on the experience and counsel of their builder’s specialised knowledge’.

The third mason’s jointing and geometry work are handled with less skill and his elements of the building are of noticeably less quality than the others. So like today, quality varied but all were masters in their own right and there seems to have been a culture of extreme ‘punctiliousness’ and artistry across the industry at the time. And this is where the personality can be inferred. The first mason was the “starchitect”, you can see it in the work. The courses of stone he cut, the geometries, and the fine detailing he was in charge of are exquisite. The third mason is highly skilled but was a bit more lax, his work is less refined than the others. However, a sense of humour comes through in what he produced. In the payment markings that his team uses on their courses, you can see caricatures of people, animals, and Kilroy was here-esque glyphs carved into them in places. The image below shows a sampling of mason marks discovered in various buildings of the Paris Basin used to identify the working campaigns of the master builders (adapted from illustrations in Chartres: The Masons Who Built A Legend (1982) P25)).

Phillip Ball in his book on Chartres, Universe of Stone (2008) states that;

“to call these men architects is almost to diminish them. Each was truly a magister operis , a master of work”.

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The kind of industriousness and craftsmanship found in the Medieval minds that built these churches and cathedrals (along with the later examples of “master building” at the crescents of Bath, Edinburgh, Glasgow, or Bloomsbury) no longer exists. Clearly, the example of the master masons is archaic and not directly applicable to construction today but two aspects of the way they worked are worth noting. The first is that the construction industry during that period operated as a highly innovative, highly responsive, network (even though it was in a prototypical form). Without telephones, faxes or computers or even measuring tapes, one man was able to direct a team of hundreds of workers. They also dealt expertly with integration with other unrelated teams’ design. The second aspect, and the one I am most interested in here, is that the master masons operated as fully integrated designer- manufacturers with great success. There was a unity within the building industry at this time which no longer exists. Now we only have fragmentation which the diagram below depicts.

This issue of fragmentation is not recent of course, it is ingrained in the culture of architecture. A gradual disintegration through time has occurred, and is still occurring. The model used by the master mason was the accepted process of building from pre-history, through the Egyptian and Roman periods, right up to the end of the Middle Ages. It is at the end of the Gothic period, and the beginning of the Renaissance, that the shift happens. At that point, the people responsible for realising buildings split in half. On one side you have craft-based guilds of builders, on the other you have liberal-arts-focused architects; two distinct and separate personas were forged. As you move forward in time from there the divergence continues into the modern era where the architectural designer role splinters further into separate disciplines of civil engineering and other sub-designers. Builders move to apprenticed trades, and down into general and specialist sub-contracting. Today, architects are even more polarised into service-led or design led practices. The fragmentation of builders continues also. There is now a very clear divorce between the design and construction of buildings.

A division of labour goes hand-in-hand with technological progress of course. Increasing complexity happens through time along with improved standards and expectations. But in the building industry, unlike others, the division of labour became pathological. I would submit that it is not since the Gothic master masons; the builder-architects of Medieval Cathedrals, palaces, town halls, guild halls and universities, that we have operated in a unified, systematic, effective, and enlightened manner. Ironically, the period in which the Gothic master builders we active is what we call the Dark Ages. We need to find ways of re-establishing the kind of integration that existed at that time.

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I suggest you seek out and explore the work of John James. His accumulated writings are vast and labyrinthine, a work of genius on a par with that of the master masons themselves.

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