The construction of the church represents a large square, and the pillars form a cross. Four immense square columns support the whole superstructure, and surrounding these are twenty-four large arches. The carved and gilded woodwork is the work of Flecha, an Italian artist. At the end of the lesser naves are domes, eight in number. The Great Dome has eight windows, with Doric columns, and it is surrounded by a balcony. An ascent can be made to the top of the dome, where there are a large lantern, a spire, and a tall weathercock above the cupola. The height from the ground is 330 feet. In the pyramidal spire, Philip II. enclosed a case containing relics of St. Paul, St. Peter, and St. Barbara. The pavement of the church is made of variegated marbles. In the reign of Charles II., the vaulting of the principal dome was pointed, but before the time of that monarch, it was stuccoed, and spangled with blue stars. Giordano was commissioned with the work of decorating this part of the building with eight frescoes. These pictures are described by O’Shea as ‘hurried, yet faithful, and the colouring very fine, though somewhat tarnished by damp.’ Later critics have, however, pointed out the traces of serious degeneration in the work of Giordano. Among the paintings are the ‘Adoration of the Magi,’ the ‘Conception,’ and the ‘Last Judgment.’ Jordaens was the artist selected to paint the works in the minor domes. It has been stated that the frescoes were finished in seven months. We need not describe each one in detail. The dome in the chief nave has a ‘Resurrection,’ in which we see the Saviour upon a throne of clouds, with the Holy Mother by his side, and from the tombs emerge the frames of the dead, some of which ascend to Paradise. In the dome over the Chapel of Our Lady there is a painting of the Virgin in a chariot, attended by maidens; and in another dome the scene is from the Old Testament, representing Joshua’s defeat of the Amalekites. The Capilla Mayor is notable for its Doric features, black marble pilasters, bronze figures, and the splendid high altar. The chief chapel is approached by an arch on three pillars, dividing it from the other parts of the edifice, and the altar is of marble and jasper. It was consecrated in 1595 by Philip II., in honour of the Blessed San Lorenzo, and within were placed the relics of San Pedro, San Tomas, San Sebastian, and other holy personages. The fine work on the screen cannot be well seen in the uncertain light; but it merits close inspection for its scheme of exemplifying all the orders of pagan architecture in jasper and bronze. Upon one division of the altar screen are two paintings by Tibaldi, the ‘Birth of Christ,’ and the ‘Adoration of the Magi.’ Tibaldi was a pupil of Michael Angelo; but his productions have little of the spirit of his master, and there is none of his work in the Escorial upon which we can write with great enthusiasm.