How an Amateur Built the World's Biggest Dome

imagine this it's 14 18 in Florence Italy you've been challenged to build a great dome for the santa maria del fiore one of the grandest cathedrals ever built and you have no formal architectural training no pressure right for Filippo Brunelleschi a goldsmith and clock maker it was the opportunity of a lifetime he considered the challenge carefully then proposed a daring plan using methods that experts don't fully understand even to this day at the time domes are often built as semi circles but the town fathers required that Brunelleschi build an eight sided dome that would be even taller and stronger it would also have no central support system to hold it up during construction even worse the domes base was an imprecise octagon with no true center but Brunelleschi had that covered there would be two domes instead of one an inner and an outer shell held together by giant brick arches and interlocking rings of stone and wood the Rings would work like hopes on a barrel keeping the dome from expanding outward to move heavy loads hundreds of feet up Brunelleschi designed ingenious new machines including an ox driven oyster and massive lifting devices far ahead of their time so revolutionary design check groundbreaking engineering check can-do attitude check but with no central support system how would he actually build it first off the masonry would have to support itself during construction to do this Brunelleschi lays the bricks in a herringbone pattern which spiraled to the top of the dome with vertical bricks acting his bookends to hold the others in place they laid about one roll a week giving the mortar time to cure at this rate the dome grew at a snail's pace of about a foot a month but perhaps most puzzling is how he was able to place the bricks with such precision many experts agree that he used guide ropes one theory states that ropes ran from a flower pattern on the work platform that showed exactly where the bricks should go another has ropes running from the dome center tracing a series of cones that grew smaller as they ascended to the top still another suggest a different arrangement of central ropes and wooden templates however it was done it worked the eight phases of the dome met at the top precisely just at Brunelleschi at planned in all it took 16 years to complete the dome when he dies in 1446 Brunelleschi left behind no sketches and no details as to exactly how he achieved his masterpiece today it remains the largest masonry dome in the world more than 500 years after it was built you you

Channel: National Geographic

Views: 2,495,816

Keywords: national geographic, nat geo, natgeo, animals, wildlife, science, explore, discover, survival, nature, documentary, duomo, build, youtube, national geographic documentary, video, Santa Marie del Fiore, Italian, Florence, NGshort14, history, construct, dome, National Geographic, Filippo Brunelleschi, Italy, cathedral, Brunelleschi, architect

Id: _IOPlGPQPuM

Length: 3min 50sec (230 seconds)

Published: Fri Jan 24 2014