+ST. PAUL’S CATHEDRAL.+ The greatest of Jones’s successors was _Sir Christopher Wren_ (1632-1723), principally known as the architect of +St. Paul’s Cathedral+, London, built to replace the earlier Gothic cathedral destroyed in the great fire of 1666. It was begun in 1675, and its designer had the rare good fortune to witness its completion in 1710. The plan, as finally adopted, retained the general proportions of an English Gothic church, measuring 480 feet in length, with transepts 250 feet long, and a grand rotunda 108 feet in diameter at the crossing (Fig. 186). The style was strictly Italian, treated with sobriety and dignity, if somewhat lacking in variety and inspiration. Externally two stories of the Corinthian order appear, the upper story being merely a screen to hide the clearstory and its buttresses. This is an architectural deception, not atoned for by any special beauty of detail. The dominant feature of the design is the dome over the central area. It consists of an inner shell, reaching a height of 216 feet, above which rises the exterior dome of wood, surmounted by a stone lantern, the summit of which is 360 feet from the pavement (Fig. 187). This exterior dome, springing from a high drum surrounded by a magnificent peristyle, gives to the otherwise commonplace exterior of the cathedral a signal majesty of effect. Next to the dome the most successful part of the design is the west front, with its two-storied porch and flanking bell-turrets. Internally the excessive relative length, especially that of the choir, detracts from the effect of the dome, and the poverty of detail gives the whole a somewhat bare aspect. It is intended to relieve this ultimately by a systematic use of mosaic decoration, especially in the dome. The central area itself, in spite of the awkward treatment of the four smaller arches of the eight which support the dome, is a noble design, occupying the whole width of the three aisles, like the Octagon at Ely, and producing a striking effect of amplitude and grandeur. The dome above it is constructively interesting from the employment of a cone of brick masonry to support the stone lantern which rises above the exterior wooden shell. The lower part of the cone forms the drum of the inner dome, its contraction upward being intended to produce a perspective illusion of increased height. [Illustration: FIG. 187.--EXTERIOR OF ST. PAUL’S CATHEDRAL.] St. Paul’s ranks among the five or six greatest domical buildings of Europe, and is the most imposing modern edifice in England.