The Bibliothèque Sainte-Geneviève opened in Paris in 1851, on the north side of Place du Panthéon. Seen from the street it is a pale stone building of two floors with a long row of arcades: it looks like a Florentine Renaissance palace. Beneath the arcades, however, the stone is covered with letters. High on the façade are carved the names of hundreds of authors, from Moses to Cuvier, in chronological order: the façade is a list of what the building contains. Whoever enters climbs to the first floor and finds a hall about eighty metres long, a little over twenty wide, carried at the centre by a row of slender cast-iron columns and covered by two barrel vaults of perforated iron. Its author is Henri Labrouste (1801–1875).
Labrouste won the Prix de Rome in 1824 and spent five years in Rome as a fellow of the French Academy. At Paestum he studied the Greek temples and proposed a reconstruction of their colours that scandalised the Académie des Beaux-Arts: for him ancient architecture was not white marble but painted surface, and history is not copied, it is interpreted. Back in Paris he opened an atelier that trained a generation of young architects, and won the commission for Sainte-Geneviève in 1838, at thirty-seven. Work lasted from 1843 to 1850.
Iron without disguise
At the time iron was already everywhere: bridges, stations, greenhouses, roofs. But nobody used it in a prestigious public building without hiding it behind stone. Labrouste does the opposite. The reading room is entirely visible iron: the cast-iron columns, very slender for their height, carry the barrel vaults, and the vaults are made of forged iron arches with perforated plant motifs that let through the light of the gas lamps and of the wide series of side windows. The iron does not act as a hidden structure: it declares itself a structure. It is a choice of constructional honesty that anticipates modernism by half a century.
The building that speaks
Labrouste's central idea is that a building must communicate its function to anyone looking at it from outside. At Sainte-Geneviève he achieves it in two ways. The façade is a long continuous wall, almost without ornament, with arcades corresponding to the bays of the hall; above the arcades, the names of the authors say “here are books”, and say which ones. You do not need to know architecture to understand what it is. In the vestibule, a perspective mural shows a garden with a sky of clouds, as if the reader were about to cross a threshold to another world, that of books. Labrouste wants a library that is legible like a book.
The next project, the reading room of the Bibliothèque nationale (1854–68), pushes the idea further: nine ceramic domes, each with an oculus, are carried on sixteen very slender cast-iron columns, and the light falls from above evenly. It is one of the most beautiful interior spaces of nineteenth-century Europe, and it remains, today, open to visitors. Labrouste never theorised functionalism and did not found a movement: he simply built, with the consistency of someone who thinks every material has a truth to tell.