Renaissance_ A Short History, The - Johnson, Paul [37]
A generation before, in 1294, the Florentines decided they ought to pull down their old cathedral and build a new and bigger one, and a plan was drawn up two years later. The façade was built of brick faced with white, green and pink marble, but work was suspended to build the campanile in similar fashion, and the old cathedral was not finally demolished until 1375. By then the final design had been settled: a vast, oblong church with four immense bays between the façade and the sanctuary, an octagonal space surmounted by a great drum with a dome on top. The cathedral, as designed, was imagined in a splendid fresco, The Church Triumphant, painted by Andrea da Firenze, a member of the planning committee. But by whom and how was this monster, unprecedented in size and raising engineering problems that had never been tackled before, to be built?
The piers for the octagon were constructed between 1384 and 1410, the drum was begun, and in 1418 a competition was held for the dome. It was won by Filippo Brunelleschi, in association with Ghiberti, who was of course already at work on the Baptistry doors. Brunelleschi guaranteed that the dome would not require construction by centering, the elaborate scaffolding process used in Gothic cathedrals to put up the stone vaults with which the masons covered large internal spaces. In fact a similar large internal space in Ely Cathedral in England, created earlier in the fourteenth century by the collapse of the central tower, had been filled by a gigantic piece of carpentry forming an octagonal lantern. But the Italians were not capable of high-level carpentry on this scale and may not have known about Ely anyway. They wanted a dome, and Brunelleschi turned to the Pantheon, the largest surviving dome from Roman times, for inspiration.
It should be understood that Brunelleschi was not, strictly speaking, the architect, since the size and form and indeed the actual curvature of the dome had been decided in 1367, ten years before he was born. He was rather the engineer or, as the contracts put it, “the inventor and governor” of the project. He was an educated man, the son of a lawyer, intended for a learned profession until his brilliant drawing led him into goldsmithing, like most Florentine artists. He had been in competition with Ghiberti for the Baptistry doors, and after his rejection he went with Donatello to Rome to study the antique firsthand. He became a master of the details, as well as the forms, and the experience led him to make architecture his chief passion. He was, then, an intellectual. But he was also a scientist, in that he brought to the dome problem considerable knowledge of the practice of stress. The dome he designed, and carried to completion in 1436, rests on eight major ribs that continue the work of the piers beneath, assisted by sixteen minor ones, all being bound by horizontal strainer arches and reinforced by metal tension chains. The angle of the dome was made as steep as its form allowed, so that its construction was self-supporting, center-work being dispensed with. To make the weight carried lighter, Brunelleschi hit upon the device of outer and inner skins, an invention of his own. Hence, although the Pantheon dome was his inspiration, it was not his engineering model, since it had been built by the usual Roman frontal-assault method of brute strength. Brunelleschi’s dome was more sophisticated, more modern. The real test of his method, however, was not just the dome’s stability but its external appearance, and it passed triumphantly. The Florentines voted it a marvel, and indeed it still dominates the city in a way that few cathedrals do these days.
Brunelleschi emerged from the dome experience as a new kind of artist—the master architect, as distinct from the craftsman or stonemason who had dominated medieval building. The architect was commissioned and paid by the patron, and he then directed and usually employed the craftsmen. Increasingly, too, the architect took charge of the