Light hoist

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Working model after Bonaccorso Ghiberti, B.R. 228 (BNCF), fols. 95r and 98v

Designed by Brunelleschi to raise light loads, this hoist consists of a horizontal wheel driven by two rods powered by four men. The shaft of the vertical wheel moves the drum on which the lifting rope is wound. The rope passes through a pulley attached to the center of the horizontal wheel. The wheel rotates around the pulley, which is fixed. The vertical wheel is fitted with Brunelleschi's characteristic cylindrical revolving gears (palei) to reduce friction.

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