St. Peter's Under Michelangelo
Upon the death of Antonio da Sangallo in 1546, Michelangelo was appointed architect of St. Peter's. Although he and Bramante had not been on friendly terms, Michelangelo recognized that Bramante's monumental conception for the new St. Peter's had been lost by the architects who succeeded him. Michelangelo took the position as architect of St. Peter's in order to see to it that Bramante's vision for the basilica was realized and refused to take a salary for his work so that he could not be fired. Sangallo's heirs were furious with Michelangelo, but he ignored them and their wrath and began redesigning the basilica and working on the dome. As soon as he took the appointment, he sent to Florence for copies of the plans of Brunelleschi's dome on the cathedral.
Michelangelo immediately returned to a Greek cross plan, simplifying the organization and increasinging the size of the piers that would support the dome. His only concession to convention was to create a temple front on the west face that would give it prominence as the primary facade.
Elevation of the south side of St. Peter's according to Michelangelo's scheme. Note that the dome at this point was still a hemisphere. Note also that Michelangelo used the giant order and attic story to unify the lower areas of the building, a far more successful solution than Sangallo's proposal.
This view of St. Peter's from the west suggests how the basilica would have looked, had it been completed as Michelangelo proposed.
Michelangelo and his pupil Giacomo della Porta built a detailed model of the dome.
By this time, the precedent of Brunelleschi's dome on Florence Cathedral had influenced della Porta to make the dome on St. Peter's melon-shaped instead of hemispherical, in order to take advantage of the more downward thrust of the melon shape.
The upper view indicates how St. Peter's would have looked if Michelangelo's plans had been realized completely. The lower view is based on further work completed in the 17th century. Note that the dome is more easily seen in Michelangelo's design than in the final solution.
Michelangelo's design for the dome was executed with only slight modification, then, by Giacomo della Porta and remains in place today. It is the largest classical dome in the world. (The second largest is the dome of St. Paul's cathedral in London, the third largest is the dome of the Capitol in Washington, D.C.).
Go to Carlo Maderno at St. Peter's in the Early 16th Century