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The “brique foraine”

Cité épiscopale d’Albi

The naturally abundant clay found in the basins of the Tarn and the Garonne Rivers made brick a common construction material in the towns built along these valleys.

In the North-West Languedoc brick buildings can be found in Montauban, Toulouse and surrounding towns. The colour of the brick changes according to the length of firing which appears to vary geographically; pale around Salvagnac; tinged with pink around Lavaur, Gaillac and Giroussens; redder in Albi and Rabastens.

From the bell-tower of Albi Cathedral, the rooftops of guttered, canal tiles offer an authentic spectacle. The Episcopal city of Albi presents a coherent ensemble composed of brick faced façades sometimes rendered with lime-wash. The use of brick in Albi is largely due to local geology and the comparative rarity of stone quarries.

However, in Roman times buildings in Albi were constructed in stone as can be seen in the base of the northern bell-tower and lateral walls of Saint-Salvi, the first parts of the collegiate to be constructed.

The nearby quarries were soon exhausted and the expense of transporting from further seams along with the difficulties posed by the Hundred Years war and the collapse of feudal society go some way to explaining the early abandonment of stone in construction from the end of the 12th century. Following the wars there was a pressing need to build quickly with inexpensive and readily available materials. The use of brick was the logical response to this problem, providing an ingenious method of rapid, solid and inexpensive construction. In addition bricks are easy to store, transport and handle on site.

The fastest construction method was timber framing in which the wooden structure was rapidly erected and the brick sections could then be filled in. The clay was trodden and kneaded to a uniform consistency by foot or by hand. This mix was then moulded into wooden frames, smoothed by hand and left to dry for several weeks prior to firing.

Finger marks can still be discerned on certain bricks testifying their hand crafted origin. In such large constructions the numerous batches of bricks were evidently not uniform in their firing which helps to explain the palette of colour; from bright red tones to pink, pinky-beige and even black for the longest fired bricks. An essential element in the construction was the repartition of bricks of different quality into a coherent whole within the structural elements. The best quality bricks were reserved for outfitting the façades and ornamental sections.

Brick is aesthetically attractive, the colour tones varying with the light and the seasons. In Albi the individual bricks have a specific form and are known as “brique foraine”. The name may derive from the fact that the bricks were fired in an oven (’four’) and thus were of better quality than non-fired bricks. On the other hand it could simply be that they were generally sold at fairs (’foires’).

The ’brique foraine’ responds to the basic requirement of an easily manipulable building unit - it weighs around 8-9 kg - but additionally, its average dimensions (5.5x22x37cm) approach the proportions of the ’golden number.’ 1 The ’brique foraine’ had a very large weight-bearing surface which allowed complete structures to be built without recourse to additional structural support in stone.

The use of brick was linked to the Gothic spirit which valued structure and technical thought. Gothic architecture decomposed the architectural art to its different technical functions, emphasising the supporting structures; arches, pillars and walls.

In religious buildings the use of brick is fully justified as it goes hand in hand with the bareness and simplicity of forms and volumes. The Cathedral of Sainte-Cécile is thus an exemplary demonstration of the art of brick construction.

The jointing technique

The timber-framing technique involves breaking the structure down into the weight-bearing timber and brickwork filling elements. The excellent quality of the mediaeval trimmings meant that a uniform external veneer could be conserved whilst the masonry joints were renewed to preserve a watertight seal. The mortar in the Middle Ages was generally of good quality; the mix of solid materials such as gravel, sand, stones from the bed of the Tarn River and slaked lime meant that the thickness of the joints could be regulated. This helped to limit subsidence which can occur due to the increasing charges the building had to bear. In the course of time the joints themselves became decorative elements – they could be recessed or in relief depending on the desired effect. In the mediaeval period masonry joints were usually pressed with the trowel blade to form a chamfer or bevelled edge which gave a neat finish and a greater bearing to the building.

During the Renaissance period masonry joints were often in relief and more elaborate. This trend bears witness to the care taken in assembling walls from brick and generally gives a greater visual effect according to the angle of the light. The use of brick alone clearly precluded rich sculpted elements; sandstone or limestone were the natural choices for highlighting certain architectural elements such as spandrels, lintels, window tracery, horizontal moulding beneath the windows...

Rendering and Lime Wash

The mediaeval bricks have been successively covered with rendering in order to protect the masonry from the elements although it occasionally also served a decorative purpose.

It was in the 18th century that the art of rendering and lime-washing with became prominent.

The rue Mariès bears witness to this evolution; here we find brickwork in which lower quality bricks were used which in the past would have been masked by the rendering whilst the better quality bricks were left visible in the corner spandrels or around the window frames. The overall illusion was therefore one of high quality masonry.

The 19th century saw a revival of the decorative use of brick in harmony with joints, often in fine pink mortar, with a very light wash of lime coloured with brick dust.

Often today we opt for restoration and the tendency is for the conservation of the exposed bricks whilst the traditional plasterwork is maintained to conserve the harmonious colour tones and balance characteristic to the Episcopal city.

1The golden number, equal to (1+√5)/2, approximately 1.618, corresponds to a proportionality which is considered particularly pleasing aesthetically. It was first found in Greek thought at the end of the 6th and beginning of the 5th centuries BC in the works of Pythagoras but it was Euclid, in his Elements, who developed a theory around this number when he attempted to define the most logical fashion of cutting a segment into two unequal but ’harmonious’ parts. For many artists, such as Leonardo da Vinci or Le Corbusier – to cite only the most celebrated – the golden number would provide the key to the harmony of a work of art. This belief was further popularised with the appearance, in 1930, of a book entitled ’The Golden Number’ by the Romanian Matila Ghyka. According to Ghyka, ancient Greek artists deliberately used the golden number, or golden section, to inspire emotion in the spectator. This would explain how the statuary and architecture of Classical Greece, the Parthenon or the Propylaea, speak so directly to our senses. Among the most fervent admirers of Ghyka’s work was Paul Valéry who was readily convinced of the truthfulness of this thesis.

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