Plans for the Altes Museum rotunda and the ground floor of the Main Library side-by-side
If one looks carefully at the Main Library's building plans, then one comes begins to see that the rotunda (Latin word for round) and circles permeate the building's design in many, many ways. Once you start looking for circles in the Main Library, you begin to find them everywhere.
On the Library's ground floor plan, the circular atrium occupies a central space, but there is also a smaller circle below the atrium, slightly to the right. On the plans this space is called a vestibule (according to the Historical Architecture Sourcebook it's "an anteroom or small foyer leading into a large space").
From the interior of the vestibule, the granite wall extends to the outside gate. Seen from outside the vestibule is a windowed space with a linear passage space with automatic doors.
Below the vestibule is the cafe on the Lower Level.
An upward view shows the windowed vestibule chamber supported by round, almost like a capital at the top of a column.
The vestibule is actually set atop two pillars above the cafe. The ceiling about the cafe has a silver circle that surrounds the lighting.
The cafe floor has a central circle and radiating spokes that are a mirroring of the atrium's floor. These expanding spoked circles directly beneath the vestibule.
source: The San Francisco Main Library: Space Planning, Design Development
The first floor also has a hidden structural round space that can be seen at the bottom center of the floor plan above (below the atrium, to the right of the vestibule).
This is a circular closet for the Friends of the San Francisco Public Library bookstore.
For regular visitors to the San Francisco Public Library Main Library building, the most frequently encountered round spaces are the affinity centers on the 2nd, 3rd, 4th, 5th and 6th floors.
The Steve Silver Music Center is typical of the rounded affinity centers on the 3rd, 4th and 5th floors. The rooms have rounded light fixtures and a circular carpet; each room has two floor to ceiling windows
The Children's Storytelling Room on the 2nd floor is another good example of these round rooms. The wooden walls follow a circular pattern as does a ring of lights, a wooden ceiling and a central circular light. The carpet below incorporates blue circles that are intersect by crimson rectangle that incorporates the effect that the 5th floor reading room has upon the atrium's ceiling.
The reference desk of the Fisher Children's Center and the suspended glass sign are also rounded.
The book display space in the Center takes the form of a circle as well.
The opposite side of the library, at the Larkin Street entrance is shaped as a semi-circle.
Inside the library's atrium there are other circles on display.
The spiral staircase connecting the Larkin Street entrance to the Grove Street entrance is formed by concentric circles. At the base of the staircase's railing there is a granite circle with a rectangle removed from it (again, like the carpet in the Children's Storytelling Room suggesting the newspaper reading room jutting into the atrium on the 5th floor).
The boundaries of concentric circles create the space taken by self-check out machines and the 1st floor information desk.
The double circle continues to extend into the floor plan of the upper floors.
It continues to be a design element on the third floor with a railing above the outer circle and an other white circle inside. At the top left hand corner of the photograph there is a portion of a smaller ring is a component of the nautilus at the top of the atrium.
Although the circle is a rather ordinary design element, it appears in many other contexts in the library.
The sign directing visitors up the stairs from the 1st floor to the Fisher Children's Center is a circular. Above it to the left, a semi-circle is used to mark the elevators and which floors they travel to.
Even the elevator call button itself is a circle.
Then there is the lighting. The pillars surrounding the atrium have round fixtures with parallel glass circles projected outward.
The hanging lamp fixtures on the 2nd, 3rd, 4th 5th floors and 6th are also circular.
Finally there are the circular structural columns that extend upward from the Lower Level to the 6th floor at the east and west sides of the atrium.
Alice Aycock's site-specific artworks commissioned for the Main Library also grow out of the circle, but they will be discussed on their own later.
The circle only plays a small role in the building's external design.
There are four metallic ornamental columns above the Library's Larkin Street entrance.
Another difficult to spot detail are the antefixes high atop the ridge of the rooftop on the Larkin and Hyde Street sides of the building that are formed from a pair of circle bisecting each other. Joseph Giovannini, in his otherwise appreciate review of the Main Library, faults these antefixes as "little doodads, vetigial Roman decoration too slight to read from Marshall Square."
Perhaps all of these circles are not worthy of special note. But they occur with such frequency that they must be more than coincidental. While they result in a degree of formal consistency and elegance, the circles create some difficulty for library users. On the upper floors, the rotunda shaped atrium disorients the public looking for a point of reference to navigate from. The round pillars on the east and west sides of the atrium are treated decoratively instead of being incorporated into a wall, thus blocking sight lines and proving to be an obstacle when arranging desks or shelving.
Bibliography:
Giovannini, Joseph, "Civic Readings," Architecture (July 1996), 80-91.
Historic Architecture Sourcebook, edited by Cyril M. Harris (McGraw-Hill, 1977).
The San Francisco Main Library: Space Planning, Design Development, April 25, 1991 (Pei Cobb Freed & Partners; Simon Martin-Vegue Winkelstein Morris, 1991). [part of the San Francisco History Center archival collection].