Built by Pius VII., in 1817, from the designs of Stern. The floor is composed of ancient mosaics, and is worthy of notice. The chief objects of interest are--5, Caryatide, supposed to be one of those which supported the portico of the Pandrosium at Athens, by Phidias; 8, Commodus; 9, Captive Dacian King; 11, Silenus; 14, Augustus, found in 1863 in the ruins of the Villa of Livia at Prima Porta; 17, Æsculapius; 20, Nerva; 23, Pudicitia, the goddess of modesty; 26, Titus; 92, Ganymedes, the cup-bearer of Jupiter; 44, Wounded Amazon; 47, Caryatide; 50, Diana; 53, Euripides; 56, Julia, daughter of Titus; 59, Plenty; 62, Demosthenes; 67, Athlete in the act of cleaning his arm with a strigil--the die, which he holds in his other hand, is an erroneous modern addition; 71, Amazon; 74, Clemency; 77, Antonia, the wife of Drusus the elder; 80, Plotina, wife of Trajan; 83, Ceres; 86, Fortune; 96, A. Marcus Antonius; 109, The Nile--the sixteen children are allegorical of the sixteen cubits at which the rise of the river begins to irrigate the land--one of the finest works of art in the Vatican, found near the Church of Minerva; 111, Julia, daughter of Titus; 114, Minerva; 117, Claudius; 120, Faun; 123, Lucius Verus; 126, Athlete; 129, Domitian; 132, Mercury. _Passing through the iron gates, we enter_ THE CORRIDOR OF INSCRIPTIONS, the walls of which are adorned with three thousand pagan and eleven hundred Christian inscriptions brought from various catacombs and cemeteries. _Retracing our way through the Museum, a glass door on the right at the entrance of the Museum conducts us to_ THE LIBRARY. _Ask the Custodian; fee, 50 cents each._ It was founded by Sixtus V., and contains 120,000 volumes, of which 25,000 are manuscripts. The magnificent great hall is 220 feet long, and contains many objects of interest, notably two fine candelabra of Sèvres china presented to Pius VII. by Napoleon I.; a vase of malachite and another of immense size, presented by Prince Demidoff; two vases of Meissen porcelain, presented by the Emperor of Germany; a large vase of porcelain china, presented by Napoleon III. to Pius IX. after it had been used as the font in the baptism of the Prince Imperial; a beautiful basin of Aberdeen granite, presented by the Duke of Northumberland. THE CHRISTIAN MUSEUM. The contents comprise a collection of lamps, glass vessels, gems, &c., found in the Catacombs. In the room beyond is a very interesting collection of Byzantine and medieval Italian paintings, a Russian calendar, and other interesting objects. At the end of this vista of rooms is a full-length seated portrait of Pius IX., painted on glass at Aix-la-Chapelle. _N.B.--The following collections at the Vatican are open only on Thursdays from nine till three; special permission is required._ THE EGYPTIAN MUSEUM.