very admirable effects may be produced in imitation of fruits, flowers, or ornaments. The use of this kind of mosaic is extremely restricted, on account of the great value and expense, not only of the materials, but of the labour employed upon them. None but the hardest stones are used; every separate piece must be backed by thicker slices of slate or marble to obtain additional strength; and every minute portion must be ground until it exactly corresponds with the pattern previously cut. THE VATICAN MUSEUM. _Open every day from 9 till 3, except on Thursday and Saturday, when it is closed. Permission must be obtained of Monsignor Macchi, at his office in the Vatican, from 10 till 1. Each permit admits a party of five, and can only be used once._ _Entrance_ is obtained by going round to the back of S. Peter's, thus enabling us on our way to admire the vast proportions of the latter. The Vatican Museum was founded by Julius II., and consists of those objects of art that have been discovered, and which once graced the principal buildings of ancient Rome. At the entrance the new official English catalogue by Signor Massi, the conservator of the galleries, can be purchased; it gives a full account of the objects of art. In so vast a collection, we call attention to the principal works only. _Entering on the left by the iron gates, filled in with glass, and ascending the marble stairs, we enter_ THE HALL OF THE GREEK CROSS. In the centre of the floor is a splendid mosaic, found at the Villa of Cicero. A bust of Minerva forms the centre, around which are twelve planets and various phases of the moon. The outer circle (modern) is composed of masks and figures. The principal statues are 559 and 597, Augustus; 564, Lucius Verus; 565, Hercules; 574, Venus of Cnidos; 566, _left_, red porphyry Sarcophagus, which contained the remains of Constantia, the daughter of Constantine the Great; 589, _opposite_, generally attributed to Helena, the mother of the Christian emperor. (See page 327.) Before the door is a fine mosaic representing a faun watering a flower. At the foot of the stairs, by two sphinxes, is a beautiful basket of flowers in mosaic. _We now enter_ THE ROTUNDA.