48 MAY/JUNE 2022
capomaestro Francesco Talenti, stalled once
again. By 1355 only the side walls and part of the
main facade of the project were anywhere near
completion. Talenti extended the main nave,
increasing the length of the church to 500 feet,
and completed Giotto’s 280-foot-tall bell tower.
The Persian Model
In 1359 or 1360 Giovanni di Lapo Ghini succeed-
ed Talenti as capomaestro. He faced the chal-
lenge of designing a dome that could cover the
huge transept. Another Italian architect, Neri di
Fioravante, came up with a proposal that would
avoid external structures such as buttresses: us-
ing rings of stone and wood hidden within the
dome’s shell. These “chains” would function like
iron rings on a barrel, preventing the structure
from splitting apart.
Fioravante’s proposal, without Gothic
additions, was pitched against the more con-
servative design proposed by Giovanni di Lapo.
In 1367 the Opera del Duomo opted for Fiora-
vante’s idea, but with a caveat: The pillars of the
transept would be enlarged, and the dome would
increase in diameter to 180 feet. Fioravante rose
to the challenge by suggesting a dome with a
double shell: a robust inner layer on which a
second, lighter skin would rest as protection
against the elements. It was the first time that
this type of design, originating in Persia and
popular in Islamic architecture, had been ap-
plied in Europe. Fioravante proposed an octago-
nal dome with eight stone ribs that that would
crown the cathedral.
Fioravante created a maquette, or scale model,
of his design, which was put on display inside
the unfinished cathedral. It became an object of
faith that the plan could and would be put into
practice. Every year, the Opera del Duomo and
its architects swore an oath on the maquette and
on the Bible, reaffirming their commitment to
complete the dome as specified. No one could
doubt their fervent support of Fioravante’s
Fioravante suggested a dome
with a double shell: a robust
inner layer on which a second,
lighter skin would rest.