Saturday, October 25, 2014

BRUNELLESCHI DOME ( CUPOLONE )

Florence began to build a new cathedral in 1296. But wars, politics, and plague slowed construction so work on the Dome didn't start for more than a century.
At the beginning no one seemed to have a viable idea how to build a dome nearly 150 feet across and it would have started 180 feet above the ground.
So in 1418 it was announced a contest for the ideal Dome design with the prize of 200 gold florins to the winner.
Filippo Brunelleschi won the contest with an ambitious project. He promised to build not one, but two Domes, one inside the other. His Dome would consist of two concentric shells an inner one visible from within the cathedral nested inside a wider, taller, external dome.
He'd build the first 46 feet in stone, after which he would continue with lighter material, either spugna or brick.

The first technical problem was how to lift the enormous heavy materials. Brunelleschi invented a three-speed hoist with an intricate  system of gears, pulleys, screws, and driveshafts, powered by a single yoke of oxen turning a wooden tiller. It used a special rope 600 feet long and featured a groundbreaking clutch system that could reverse direction without having to turn the oxen around. He made also other innovative lifting machines, like the castello.
On March 25, 1436, The Feast of Annunciation, Pope Eugenius IV consecreted the finished Cathedral.
Ten years later another illustrious group laid the cornerstone of the lantern, the decorative marble structure that Brunelleschi designed to crown his masterpiece.
Brunelleschi died in 1446 and was buried in the cript of the cathedral.


We can see a particular reproduction of the Dome at Parco dell'Anconella, a nice natural area in the south of Florence.