Page:Character of Renaissance Architecture.djvu/281

Rh not, indeed, very close; for Wren has raised the springing so that it is almost at the top of the drum, but he has fortified it with a continuous abutment which, though of different outline, has substantially the same structural effect. The likeness to St. Peter's is further shown in the encircling order of the inner face of the drum, which occurs in both Bramante's scheme and in that of Michael Angelo. There can be little doubt that Wren had studied Bramante's design in Serlio's book, and had appreciated its structural merits. But he wished, in emulation of Michael Angelo, to make his dome externally more imposing, and he therefore raised its springing level as we see, and adopted from Michael Angelo's scheme the idea of a double dome. The external outline from the top of the drum to the haunch of the vault is too nearly the same as the corresponding part of Michael Angelo's design to be considered as an accidental coincidence. The structural difference between the two is indeed great, since the concave portion in Wren's design is a continuous ring, while in that of Michael Angelo it is an isolated and insignificant abutment. Wren's scheme is thus superior in point of constructive merit, since it provides continuous resistance to continuous thrust. It will be seen that the two shells of Wren's projected dome correspond to the inner and outer shells of Michael Angelo's model (Fig. 26, p. 54), and thus in reproducing the main idea of this model Wren merely omitted the middle shell. He thus gave a wider divergence to the two vaults as they rise than occurs in the actual dome of St. Peter's. He also omitted the well which in St. Peter's connects the two shells at the crown.

A single order of pilasters adorns both the interior and the exterior of the church itself, the one on the outside being raised on a high basement and crowned with a plain attic; and a portico in the form of a temple front, with its order raised on high pedestals, gives emphasis to the west façade.

This design appears to have been rejected, to Wren's great chagrin, as we learn from the following passage in Parentalia: "The surveyor in private conversation, always seem'd to set a higher value on this design, than any he had made before or since; as what was labour'd with more study and success; and, (had he not been over-rul'd by those, whom it was his duty to obey), what he would have put in execution with more