Mr. Carnegie's greatest gift has been the Pittsburg Library. It is a magnificent building of gray Ohio sandstone, in the Italian Renaissance style of architecture, with roof of red tile. The architects were Longfellow, Alden, and Harlow, their plan being chosen from the one hundred and two sets of plans offered. The library building is 393 feet long and 150 feet wide, with two graceful towers, each 162 feet high, and has capacity for 300,000 volumes. The entire "stack" or set of shelves for books is made of iron in six stories, and is as nearly fireproof as possible. The lower stories are for the circulating-books; the upper stories for reference-books. The library proper is in the centre of the building, reached by a broad flight of stone steps. Above, cut in stone, are the words, "Carnegie Library; Free to the People." The vestibule, finished in marble with mosaic floors, is handsomely decorated. On the first floor are the circulating-library, "its blue-ceiling panels bordered with an interlace in orange and white," a periodical room on either side, one for scientific and technical, the other for popular and literary magazines, with rooms for cataloguing and for the library officials. "The reference reading-room on the second floor, large, beautiful, and well-lighted," says the efficient librarian, Mr. Edwin H. Anderson, "is for quiet study. Here reference-books, such as encyclopædias, dictionaries, atlases, etc., are at hand, on the shelves along the walls, to be freely consulted." This room is of a greenish tone, with ivory-colored pilasters and arches, and a _fleur-de-lis_ pattern painted in the wall-panels, from the "mark" of a famous Florentine printer and engraver four centuries ago. Across the corridor from the reference reading-room are five smaller rooms for special collections of books. One is occupied by a musical library of two thousand volumes, of the late Karl Merz, which was bought and presented to the library by several citizens of Pittsburg. Another will contain the collection to be purchased from the fund left by Mr. J. D. Bernd, and will bear his name. Another will be used for art-books, and another for science. The children are to have a reading-room, made attractive by juvenile books, magazines, and copies of good pictures. A large and well-lighted room in the basement is used for the leading newspapers of the country. The library has a wing on either side, one containing the art-gallery, and the other the science museum. The former has three large picture-rooms on the second floor, painted in dull red, with a wall-space of 8,300 feet for the exhibition of paintings and prints. A corridor 148 feet long, in which statuary will be placed, is decorated with copies of the frieze of the Parthenon. The basement of this wing will be devoted to the various departments of the art-schools of Pittsburg.