The main reading room's floor plan, beautifully presented in the exhibit in an 1850s pen and ink and graphite wash drawing, is starkly utilitarian, almost Miesian. An early version of the plan from 1842 shows a more robust enclosure with a deeper poché. The 1850 plan drawing has almost no poché—highly unusual for a Beaux-Arts orthographic.
The organization of the library is rigorously linear, not classical in proportion, with an appendage on the back housing a grand stair. It is as if the space that Labrouste contains with these walls is pushing against its container, compressing the thinness of the envelope.
The exterior of Sainte-Geneviève expresses the nature of the thin masonry wall: the facades have expanses of smooth stone, low-relief carving, windows with thin surrounds of modest depth, delicate ornament that reads more as two-dimensional than three.
The library's enclosure clearly articulates the expansive reading room on the upper floor. Between the windows, one can detect the structure's iron arches tied into the masonry wall with metal pins visible on the exterior. In a very Modern vein, Labrouste articulates the interior contents on the exterior. Stone panels between the windows around the building bear the names of 810 authors, carved to suggest books stacked on the shelves of the reading room.
An Early Modernist
The MoMA exhibit also traces Labrouste's influence on architecture. The exterior of the Boston Public Library, designed by Charles Follen McKim and completed 45 years after Sainte-Geneviève, reveals the influence of Labrouste's design, but without its delicacy. The repetition of the reading room windows across the façade, the understated main entry, and even the carved names of authors are all there, but it has repose, rather than the lightness and buoyancy of Sainte-Geneviève.
Central to Sainte-Geneviève but not expressed on the exterior, are twin barrel vaults that stretch from one end of the reading room to the other. They provide the airy atmosphere of Labrouste's main space, but they are not supporting much more than themselves and the delicate roof framing. The beautiful structural drawings on exhibit show how the vaults are sheltered under the building's low-pitched roof, which is concealed from the interior and hidden beyond the cornice at the apex of the facades.
The space prefigures the great train sheds to come, and Paxton'sCrystal Palace in London completed a year later (which surpassed Sainte-Geneviève in its structural daring). But Labrouste's breakthrough, as the MoMA exhibit documents, was an interior that was essentially independent of the exterior walls, allowing the envelope to be thin and the poché typical in Beaux-Arts masonry buildings to vanish.
Bibliothèque nationale de France
Nearly a decade after the completion of Sainte-Geneviève, Labrouste started work on the renovation and addition to the Bibliothèque nationale de France, which would occupy him for the rest of his life.
Where Sainte-Geneviève is linear in its spatial expression (like Kahn at the Kimbell Art Museum), the reading room at nationale is volumetric--tents of space through which filters natural light captured from above (like Pelli at Reagan National Airport). Where Sainte-Geneviève is an extrusion of space, the nationale is multi-dimensional, defining space with 33-foot-tall, spindly iron columns crowned with squared ceramic vaults that seem as thin as eggshells.
Where Sainte-Geneviève suggests the thrust of the fast-moving train of new technology--cast iron, lighting, heating, and other architectural wonders—the nationale exhibits a more ancient form of space-making. Where Sainte-Geneviève is the library as tunnel, nationale is the library as temple.
The reading room at the nationale lifts itself to the title of the exhibit: structure brought to light. Each of the nine squared vaults has an oculus that floods the reading room with pools of natural light, making the domes appear weightless. Like Sainte-Geneviève, there is a concealed roof above the curved surfaces, which admits light through skylights, delivering it to the oculi of the domes.
Further experimentation with new materials is found in Labrouste's new stack space. Here the architect created an iron framework of shelves, floors, and stairs, perforated under a skylit ceiling to allow illumination to penetrate the stacks: literally illuminating the word. Labrouste used pneumatic tubes to shuttle book requests to the stacks for retrieval, all revealed through a glass wall into the reading room.
Labrouste's interest in what architecture is made of, revealed as a student, is a touchstone through his evolution as a designer. He is one of the first in a long line of Modernists, willing to experiment with technology to make architecture new, yet timeless.