Dome

Pathway between enclosure all on the right and the tower area, with pergola arching overhead; It is the largest building in the world reserved exclusively for the preservation of rare books and manuscripts. The six-story above-ground building is supported on four massive piers at the corners of the building, which descend 50 feet to bedrock. The books stacks are contained within a glass-enclosed tower in the center of the building (closed stacks only); materials are brought to patrons by staff in the basement level ("court level") reading room, which is ringed with windows and lit by the courtyard which opens into the plaza, surrounded with a low wall. There is another basement level for staff. The lobby area around the glass tower is used for exhibits. The interior is lit in part by the translucent marble slabs, which transmit an amber glow. Source: Wikipedia; http://en.wikipedia.org/wiki/Main_Page (accessed 8/6/2013)