Below the steps of the altar, and, of course, some distance from it, at the corners, on four massive pedestals, four twisted pillars, 50 feet in height, rise and support an entablature, which bears the canopy itself, topped with a cross. The whole is 95¼ feet from the pavement. This brazen edifice--for so it may be called--was constructed of bronze stripped from the dome of the Pantheon, and is so disposed as not to obstruct the view by concealing the chancel and veiling the chair of S. Peter. This ornament is also of bronze, and consists of a group of four gigantic figures, representing the four principal doctors of the Greek and Latin Churches, supporting the chair at an elevation of 70 feet. Under the high altar of S. Peter's is the tomb of that apostle, the descent to which is in front, where a large open space leaves room for a double flight of steps. The rails that surround this space above are adorned with one hundred and twelve bronze cornucopiæ, which support as many silver lamps, burning during the day in honour of the apostle. Upon the pavement of the small area enclosed by the balustrade is the kneeling statue of Pius VI., by Canova. DIMENSIONS. _Interior._ 613½ feet long. 152½ feet, height of Nave. 87½ feet, width of Nave. 33¾ feet, width of Aisles. 197¾ feet, width of Basilica. 446½ feet, length of Transepts. 95¼ feet, height of Baldacchino complete. 139 feet Cupola, interior diameter. 179 feet Cupola high. 277 feet above Floor. 440 feet from Pavement to Base of Lantern. _Area._ 240,000 square feet. [Illustration: INTERIOR OF S. PETER'S.] A PROMENADE IN S. PETER'S. On entering, the size of objects may be judged by noticing the cherubs that support the holy water basins; they present no extraordinary appearance, but stand by them and their immense size will be appreciated. The first chapel, on the right, contains Michael Angelo's Mary with the Dead Christ; hence it is called the Chapel of La Pietà. It was executed by the great master when only twenty-four, and bears his name across Mary's girdle. This work of art is unfortunately very badly placed for proper observation. Opening out of this chapel are two side chapels, kept closed: in that of the left are kept the relics belonging to the basilica; and in the right, a column, ornamented with flutings and reliefs, and said to be the column against which Jesus leaned when disputing with the doctors.