When people talk about the "infinite construction of the Duomo", they are referring to the many centuries (from the end of the 4th century to the middle of the 20th century) which it took for the Cathedral to be completed and to the ongoing maintenance and restoration which it requires to this day. In fact, the centuries during which the Duomo was being constructed were defined by a feverish construction site which was the engine fuelling most of the entire city's economic life, as evidenced in the Archives of the Veneranda Fabbrica where the daily testaments of this period in history are collected and preserved.
A construction site of such impressive size, within an urban context that was quite different from that which now surrounds the Duomo, must have had quite a substantial impact on the life of the city. All around the site, which, as it grew, progressively absorbed the ancient Basilica Maior di Santa Maria Maggiore, was a lively neighbourhood of shops, marble workers' laboratories, carpenters, and glaziers: a ceaseless activity skilfully coordinated and managed by the Veneranda Fabbrica which, in addition to everything else, also ensured that the area around the site was kept clean and in order. What complicated this task considerably was the extraordinary variety of vendors, artisans, and merchants that populated the streets around the Duomo. These included the "boiacherii", or those who prepared and sold "boiacca", a type of grout made of chalk, water, and lime which was used as plaster and as a fixative by carpenters.
In the memorandum shown here, dated 26 January 1589, the Chapter mentions having previously told a certain Antonio Bosisio to stop selling boiacca in the church's piazza, but, it would seem, to little effect. The realization that their warning had been disregarded led to more forceful action: first, the Veneranda Fabbrica prohibited that boiacca be mixed in the piazza and then, more generally, insisted that the streets around the future cathedral be kept clear of any and all obstacles and especially trash. Such an ordinance was certainly nothing new among the Fabbrica's resolutions and even in the centuries to come the Fabbrica would revisit the issue repeatedly, as demonstrated by several entries published in the annals.