Let’s pause to give some thought to the mureri who built these chimneys, and to those whose job it was to keep them clean, the scoacamini. (If you walk down the Calle dei Scoacamini in San Marco, you are in the area where the chimney sweeps used to live.)
The confraternity (scuola) which controlled these trades, I Mureri was established by 1200, making it one of the oldest of the scuole . There is a bas-relief on the facade of the building at Salizada S. Samuele, 3216 showing the tools of their trade: the hammer, trowel and “archipendolo”, which I take to be a plumb-bob.
For the apprentices in these trades, the final exam, in order to become a master, was for the the murer to build a fireplace, and for the scoacamin to show he was capable of the proper maintenance of fireplaces, which would have included cleaning the chimneys.
Many of the chimneys we see in Venice are still functional, but most are in need of restoration and maintenance. Due to the fact that building materials in Venice tend to be re-used (often many times), it is hard to date any particular chimney. However, the chimney we can see emerging from the roof of the Biblioteca Marciana is ascribed to Sansovino, who died in 1570.