"Il Lanificio" (The Art of Wool) by Mirabello Cavalori. 1573, Palazzo Vecchio, Florence.
This is a superb rendering of the many steps involved in processing and dyeing wool. The colorful clothing may be symbolic, but it is still noteworthy that here, for the first time, we have people clad in very little working in a dye shop. Given the sartorial dangers of the trade, this would be much safer than the apron shown worn by others.
To the right is the familiar round vat. The furnace fire is being stoked by one man, while three others stir it energetically with long sticks. The lack of color in the vat indicates that the wool is most likely being mordanted or alumed.
The square vat behind the furnace was used to wash the wool before entering it into the dye bath.