Lantern crane with annular platform

Conceived by Brunelleschi, but constructed only after his death in 1446, this crane has been reconstructed as an operational model in 1:2 scale. It was used in the construction of the conical cusp of the lantern on the Florence Cathedral dome.

The machine is equipped with a rotating annular platform and is capable of lifting marble slabs and positioning them all along the perimeter of the cusp.At the end of the arm, a worker rotates the wooden disk that functions as a screw bolt, causing the advancement or retraction of the screw and the slide connected to it. This operation makes it possible to move the slabs horizontally.Below, making use of two windlasses that mesh with one other through a toothed wheel and pinion system, another worker drives a system of cables and pulleys connected to the slide, thus allowing the crane to lift and lower the marble slabs along the inclined surface of the lantern cusp.