In 1784 Étienne-Louis Boullée (1728–1799) drew a project nobody had commissioned: a cenotaph for Isaac Newton, who died in 1727. It is a sphere. In the drawings it measures about 150 metres in diameter and rests on a circular base planted with cypresses. Inside, it is completely empty, with a perforated vault: by day light enters through the holes and draws a starry sky on the ceiling; at night, a great armillary sphere hung at the centre lights the interior like a sun. Boullée writes that architecture is the art of producing sensations. A sphere is perfect and infinite, and as such suited to celebrating the man who measured the universe.
The cenotaph is impossible to build with eighteenth-century techniques, and Boullée knows it. He does not care. His aim is another: to show that architecture can be, before it is a building, an idea with a form. For this reason he chooses elementary volumes (spheres, cylinders, pyramids, cubes) and takes them to monumental dimensions, obtaining effects of light and shadow described in his plates with a painter's care. His treatise, Architecture, essai sur l'art, would remain in manuscript and be published only in 1953.
Ledoux: the city around the factory
Claude-Nicolas Ledoux (1736–1806) is luckier at building. In 1775, for Louis XVI, he designed the Saline Royale at Arc-et-Senans, in the Jura: a saltworks with a semicircular plan, in which the director lives at the centre, in a building with a Doric portico, and the workers in the buildings fanning out around. The idea is that the form of the factory determines the life of those who work in it, and communicates it: architecture as an instrument of social order. The saltworks functioned until 1895; today it is a UNESCO World Heritage site (since 1982). Only half of the circle, however, was built: Ledoux was thinking of a complete ideal city, Chaux, drawn in the following years with buildings in the form of cylinders, spheres, pyramids.
The barrières: fiscal power in stone
Ledoux's most exposed project is the one that made his fame odious. Between 1785 and 1789 he built about sixty toll houses (les barrières) along the new wall of the Farmers-General around Paris: stone buildings with porticoes, cylinders, columned pediments, in which the tax authority collected duties on incoming goods. Parisians hated them: the wall was a symbol of fiscal power, and with the Revolution many were set on fire. Ledoux himself was arrested in 1793 and narrowly escaped the guillotine. Today four remain, including the Rotonde de La Villette and the two pavilions of Place Denfert-Rochereau.
For a century and a half the two architects were forgotten. In 1933 the Austrian historian Emil Kaufmann rediscovered them in the book Von Ledoux bis Le Corbusier, arguing that they are precursors of modern architecture: elementary geometry, absence of superfluous ornament, building as manifesto. Aldo Rossi, in the 1960s, made them a direct reference, and the cubes, cylinders and pyramids of his buildings are in part children of those plates. Boullée and Ledoux's vision has returned, ever since, whenever architecture has sought a primary, essential language charged with meaning.