The lantern glasses were changed in the Middle Ages every fifty or sixty years and only for this work in 1405 more than half of the annual Fathers of the Commune spent some sort of superintendence on public goods and urban planning.
On that occasion 913 glass disks from Altar and Masone had been used for a weight of 188 rubles (15 quintals) and 1380 rubles (110 quintals) of lead.
Along with the glasses, set up along a continuous circular iron wall with iron posts, the fifty-two lamps were also replaced which burned the precious so-called Doge oil guarded in the Ducal Palace’s bottoms. Lastly, in the ordering of this restoration there were wicks that were lit with a spark plug.
Then above the lantern there was a wooden roof, resting so as to allow the passage of the air to draw and every night the torrexan controlled that the wicks were of the right size to burn properly: neither too fast nor too much slowly.
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