In Mr. Simmons’s panels, each of the Muses is shown as a seated figure. On either side a laurel wreath is displayed, as the general symbol of intellectual pursuits, and the background is diversified by curving lines of smoke proceeding from the flame of a torch or a censer--thus signifying the inspiration of Art and Poetry. In several of the tympanums the Muse is accompanied by little geniuses who serve to bring out the special character of the central figure. In the panel devoted to Thalia the genius is a satyr, with goat’s legs, and carrying a pair of Pan’s pipes. The Muse playfully catches him in a fold of her garment--the whole suggesting the rustic sportiveness of the early Greek Comedy. Certain of the panels, also, contain various distinguishing objects. Melpomene, for example, is accompanied by a tragic mask; Clio by a helmet, for the warlike exploits recorded by History; Thalia, by a comic mask; Urania by a celestial globe. Terpsichore is represented as if swaying to the music of the dance, and is striking a pair of cymbals. Erato is nude, and bears a rose--the flower of love--in her hand. Polyhymnia holds an open book in her lap. One of the geniuses in the tympanum of Calliope holds a scroll, and the other some peacock’s feathers--the latter symbolical, perhaps, of the dignity and beauty of the Epic. SPECIAL ROOMS. Of the two rooms leading from this corridor--the Northwest Gallery and the Northwest Pavilion--the first is decorated in a cheerful spring-like green ornamented with garlands, and the Pavilion in a deep Pompeiian red with medallions containing figures of dancing girls, by Mr. R. L. Dodge, and conventional ornaments adapted from Pompeiian designs. In the six window bays, also, is the series of the signs of the zodiac, designed by Mr. Thompson. The various galleries and pavilions on this floor, excepting, of course, the Congressional Reading Rooms, are designed to accommodate the clerical and cataloguing work of the Library and the Copyright Department, or to furnish room for special collections of books. There is every reason to hope that in time many valuable private libraries throughout the country will find their permanent home in some one of these apartments, given or bequeathed by their owners to the Nation, and preserved for all time in convenient, well lighted and fireproof rooms as a memorial to the liberality of their donors. Already one such collection has been received, presented several years ago to the Library by the late Dr. J. M. Toner of Washington. It is kept by itself in the Northeast Pavilion. The most remarkable feature is its Washington letters, gathered either in the original or in copies, during a period of many years. THE BASEMENT.