The cathedral of St. Paul as it now stands was never embodied in any set of drawings. Starting with a few rough sketches the scheme was developed as the work proceeded, the master being always present to direct the work. Wren was at the start what would now be called an amateur, but by degrees he learned his art in the best possible way, not in the office or drawing-room, but on the scaffold in close contact with the works. It was thus that Brunelleschi had worked on the dome of Florence, and Michael Angelo on St. Peter’s. The plan of the existing St. Paul’s has no beauty comparable to that of St. Peter’s (Fig. 31, p. 67). It has a long nave with a short transept near the middle, a semicircular apse, and two western towers. Both nave and transept have side aisles, and in the angles formed by the towers, which project beyond the aisles in the manner that is common in the mediæval churches of England, are a consistory court and a morning chapel, while in the angles of the crossing three vestries and a stair-turret are set. Thus the Greek cross plan which Wren appears to have first intended, “a long body with aisles” having been “thought impertinent, our religion not using processions,” was widely departed from in conformity with the popular feeling that the first plan “deviated too much from the old Gothick form of Cathedral Churches, which they (the people) had been used to see and admire in this country.” In the elevation a great dome, in outline not very unlike the one first intended, rises over the crossing; the nave and aisles are vaulted with small domes on pendentives of peculiar form, and the piers of the interior are faced with a great Corinthian order of pilasters. That Wren worked with constant reference to St. Peter’s as the main source of his inspiration, is clearly enough manifested in the general scheme, though there are many points of difference between the two monuments, apart from the great difference of scale. Other sources of influence are, however, also apparent. The most interesting feature of St. Paul’s cathedral is, of course, the great dome (Plate XI), which is one of the most remarkable of the series of modern domes that began with the dome of Brunelleschi. In general external form it recalls Bramante’s diminutive circular temple of San Pietro in Montorio, and it is not unlikely that Wren derived the idea from the woodcut of that design in Serlio’s book, or in that of Palladio. Wren has, of course, altered and amplified the scheme in adaptation to his vast scale and lofty proportions, but the general composition of the two is substantially the same, though the internal structure is entirely different. The leading features of the exterior, the encircling order crowned with the balustrade, and the dome rising over it surmounted by the lantern, are those of Bramante’s design. [Illustration: FIG. 136.--Section of the dome of St. Paul’s.]