Page:The Carnegie institute and library of Pittsburgh (1916).djvu/25



volumes for circulation are kept in the book stack adjoining. A complete card catalogue of circulating books is kept in this department.

The book stack is 11 stories high, capacity about 800,000 volumes. It is fire proof and as nearly dust proof as possible. All windows are hermetically sealed and the air is washed before being forced into the stack. An automatic electric elevator connects all floors.

, on second floor. The room is 91 x 44 feet with a wing 68 x 32 feet. It is furnished with 20 reading tables, and chairs for 136 persons. On shelves about the walls are 10,000 volumes free of access to all. Over 65,000 more volumes are in the stack. A complete