Understanding the system of alphabetical and numerical co-ordinates used on the floor plans will help you locate what you are looking for in the buildingwhether a book, a carrel, a room, or a collection other than (F) that is located in the Firestone Library, such as the Classics Collection (Clas), the Periodicals Reading Room (PR), and many others.
When you step out of a public elevator on the Third Floor, A Floor, or B Floor, look down at the large floor tile representing a compass card to orient yourself.
With the exception of the Main Floor, the floors are made up of sections that measure approximately 18 by 25 feet and are ordinarily defined by a large pier at each corner. These piers are represented by black rectangles on the floor plans.
The floor plans show rows of sections running north and south and marked from 1 to 19. B and C Floors have two additional rows of north-south sections on the west side that are marked I and II.
The lettered rows run east and west and are marked from A to J (I is omitted) above B Floor and from A to P (I and O are omitted) on B and C Floors.
Some sections are subdivided into spaces for carrels and offices. Co-ordinates for those spaces include a number after the row letter: 3-10-G-8 is a carrel in section 10-G on the Third Floor.
The green Call Number Information sheet and the large green call number guides that are posted near the main elevators indicate the co-ordinates of the section in which the books at the beginning of a given range of call numbers are shelved. The plan for the floor specified in the co-ordinates will help you understand how all of the books in that range are shelved, where books in other call number ranges and in collections other than (F) are shelved on that floor, and where you will find bathrooms, photocopiers, telephones, and other services and offices.
Please do not hesitate to ask any member of the Library staff for help in using the Main Catalog or finding materials in the libraries.