A preserved heritage brought back to life

A preserved heritage brought back to life

Bourse de Commerce

The dialogue between heritage and contemporary creation, at the heart of the architectural project of Tadao Ando, started with the restoration of a rediscovered, magnified historic site.

The restoration of the state of the building as it was in 1889

“The Bourse de Commerce in Paris is remarkable for several reasons. In the various historical strata it displays, the building stands as an iconoclastic work. Its exterior shows the additions of each era: the column of the former Hôtel de Soissons (built by the architect Jean Bullant for Catherine de’ Medici in the 16th century), the circular surface and interior façades of the first Halle au Blé (constructed by the architect Le Camus de Mézières from 1763 to 1767), the iron cupola, conceived by the architect François-Joseph Bélanger and the engineer François Brunet from 1806 to 1813, and finally the exterior façades, the roofing, the inner layout and the decors produced by the architect Henri Blondel, during the transformation of the edifice into the Bourse de Commerce, in 1889.

The building is not just a simple superposition of these historic strata, but rather a fusion of eras. For example, during the transformation of the Halle au Blé into the Bourse de Commerce by Blondel in 1889, the doublerevolution staircase of Le Camus de Mézières was extended and included in a new, modern system of movement, while Bélanger’s metal structure — one of the greatest technical feats of the early 19th century — was given a glass ceiling and a painted decor.
In this way, the Bourse de Commerce is a manifesto for the Parisian architecture of the 16th, 18th and 19th centuries, recognised by several levels of protection: the listing of the Medici column in 1862, the inscription of the site in its entirety by a decree on 15th January 1975, while the cupola and its decor were listed by a decree on 20th June 1986. […]

“In the various historic strata it displays, the building stands as an iconoclastic work.”

An initial programme of probes of the building allowed for the completion of the analysis of the exterior and visible parts. […] These investigations into the structure were necessary because of the lack of construction documents from 1889. Both in archival research and on-site investigations, these non-destructive approaches succeeded in “reading” the building without damaging it. Materials which were common in the late 19th century, but which are almost all lost today, were thus recovered. […] The exterior façades came in for additional investigations, allowing for the identification of the Saint‑Leu stone they are made of.

The key moments and aspects of the restoration

The Medici Column : an icon

“The so-called Medici column, alongside the exterior façade of the Bourse de Commerce, is an icon of the Parisian landscape. Thanks to his demands regarding the column, the writer Louis Petit de Bachaumont is credited with the very first move in history in favour of its conservation. Publicly opposed to its destruction in 1748, he for the first time showed the attachment of Parisians to this large vestige of the former Hôtel de la Reine. The column became a listed monument in 1862, breaking with the history of the building beside it, then was once again conserved when part of the building was demolished in 1889. […]


Between 1574 and 1584, Queen Catherine de’ Medici entrusted the architect Jean Bullant with the extension of the existing palace […]. In a small courtyard, she had built the first self-standing column in Paris, as a sign of her power in the town. At the time, the observation platform was accessed through a door communicating with the Queen’s palace and a spiral staircase, topped by a ladder, two metres from the top. Today, the spiral staircase still communicates with the second floor of the Bourse de Commerce, via an arched passageway of a few steps.

Colonne Médicis
Drawing attributed to Alexandre Lenoir illustrating the inclusion of the column in Nicolas Le Camus de Mézières’ project.

Inspired by Trajan’s Column (put up in Rome in the late 2nd century BCE in the former forum of the Emperor Trajan), it is made from Oise limestone, with regular supporting blocks, infilled with plaster, as was shown by analyses of several fragments. Its base has no ornamentation, while the summit is decked with grooves, crowns, fleurs-de-lis, cornucopias, numbers, broken mirrors and coats of arms. In the upper section, there is a capital-platform topped by a metal structure. […] While the monument is appreciated, its function has never been identified. The column may have been an observation post for the Queen’s astrologer, Côme Ruggieri, even though this hypothesis has not been proved. […] In 1764, it was equipped with a sundial designed by Alexandre-Guy Pingré […] then it became a public monument when it was given a fountain in 1812, which has since disappeared. The current restoration aims at a strict conservation, by keeping the materials and all of the succession of reparations conducted from 1925 until 1981.”

The Halle au Blé : a circular utopia

“The programme for the Halle au Blé was drawn up in 1763 on the site. It was part of a new urban awareness, affirming the importance of public interest, which was developing in the second half of the 18th century. The construction of the hall and its surroundings was entrusted to Nicolas Le Camus de Mézières, an expert architect, sworn to the king and to his university. The resulting building was utterly original, in its urban setting. […]

The first public monument designed in the centre of a neighbourhood of rented accommodation, accessed by a star-shaped network of streets, the project based its originality on the will to make two halls in one, thanks to a building with arcades around a central courtyard. The choice of a ring design alludes to the figure of the circle, which during the Enlightenment, stood out as one of the basic models of architectural innovation. It broke away from the traditional schema of rectangular naves. […] 

La Halle au blé en cours de transformation
The Halle au Blé during its transformation in 1887: all that is left is the inner ring, the metal structure of the cupola and the Medici column.

The Medici column was included in one of the mantels of the exterior façade of the Halle au Blé. This rigorous step, which brought together the antiquity of the 16th century and the new construction of the 18th, introduced an irregularity into the strict rhythm of the building’s arches. Since then, all the constructors who have acted on the building have been confronted by the variation that the column eternally effects on the construction system. […]

The interior façade forms an archaeological reservoir of the 18th century project. Its cladding, around the rotunda, was recomposed by Blondel so as to form a new elevation with three levels. The other side of this interior façade was stripped bare during the restoration, showing up the fixtures and techniques chosen by Le Camus de Mézières. […] The architect flanked the hall with two double-revolution staircases, one to the east, the other to the west.”

 

The Cupola, from wood to iron : a feat of architecture and engineering

“Le Camus de Mézières’s Halle au Blé stands as an architectural manifesto with a radical schema: a ring-shaped hall, open in its centre towards a vast circular courtyard. New needs, resulting from the use of the hall rapidly led to its modification, making the Halle au Blé a structural laboratory: in succession, it gained a wooden cupola in 1782, then a cast-iron one, made in 1811 by François-Joseph Bélanger and François Brunet, with the assistance of Jacques Ignace Hittorff, the future chief architect of Paris during the Second Empire. This metal cupola—which can still be seen today—was the first ever construction made from this type of material, as a symbol of the industrial century that was being born.

Jacques Ignace Hittorff led the cupola project, under the direction of Bélanger, and left behind an exceptional drawn record of his contribution.
Our documentary research revealed the importance of a little-known iconographic archive, conserved at the Wallraf Richartz Museum in Cologne.
It includes two hundred and forty drawings. Many other documents seem to be associated with the production of cast-iron elements (made by the forges of Le Creusot). […] These drawings provided decisive support to the project for the restoration of the frame, in a mixture of cast and forged iron. […] As well as studying these archives, a series of samples were taken from the current frame. Initial exploration made by a drone provided an immediate diagnosis of the structure, before the drawing-up of a surveyor’s study using a laser, which confirmed the absence of any previous or structural deformation to the overall modelling of this frame. […]”

Pierre-Antoine Gatier, Chief architect of French historic sites, project manager. 
Extract from La Bourse de Commerce, Paris, co-published with the Bourse de Commerce — Dilecta, bilingual, to be published in 2021.