National Geographic : 1923 Jun
578 THE NATIONAL GEOGRAPHIC MAGAZINE F, w iIIII . Photograph by Charles Martin TIlE GENERAL READING-ROOM OF TIIE LIBRARY OF CONGRESS The rotunda is 1oo feet in diameter, and at each of its eight angles rise clustered piers of red Numidian marble resting on bases of brown Tennessee stone and supporting semicircular arches that bear the massive entablatures, from which spring the ribs supporting a great dome of copper. In addition to its three million books, the library contains collections of prints, maps, manuscripts, music, and books for the blind. There are 102 miles of shelving in this, America's National Library, where two copies of every copyrighted book are deposited, the books catalogued, and the printed catalogue cards distributed among the libraries of the country. Books needed in any part of the United States are furnished to institutions through their local libraries. There is an average of three thousand visitors each day (see Color Plates I and XI).