The Bologna water system in 1200 was very important for the diffusion of water to the many silk mills present in the city.
Silk is a natural fiber produced by the maggot to form the cocoon.
Since ancient times, this wire along a few hundred meters, was carried by the cocoon, through a first processing, called silk reeling.
For this operation they needed a basin and a reel.
From the basin that contained the cocoons in the hot water, a worker formed with a dozen wires a single thread that another wrapped around on a reel forming the hank.
Progressively the silk reeling centered on large spinning mills where dozens of workers performed the work with increasingly sophisticated machines.
Before weaving the yarns underwent further processing; one or more yarns were waxed and compacted through repeated twists.
This operation, called twisting, was traditionally done by hand or with the help of small household instruments such as the spindle.
However, in Bologna since the 300's, silk twisting was used for a complex machine of lucchese origin, the round spinning yarn.
It was a machine with arms folded, which allowed to twist the threads of hundreds of spools simultaneously.
At the prototype of Lucca the citizens of Bologna applied the hydraulic wheel and thus the small spinning-yarn placed in a room turned into silk mills arranged on three or four floors of buildings in which dozens of workers were crowded.
The yarns could only use wires wrapped in spools.
The transfer of wires from the hanks to the spools, called the spooling, was done by hand by women working in their homes.
This manual operation because of its sluggishness created a slowing of the production cycle only partially mechanized.
In the 500 in Bologna to solve this problem was introduced the mechanical shelf powered by thet ransmission organs of spinning wheels.
The silk mills in Bologna with hydraulic wheel and mechanical crank were particularly efficient as they increased production rates and guaranteed better quality yarns.
The constant speed of the hydraulic wheel, ensured by a regular flow of water, made it possible to obtain uniformly twisted and more resistant yarns.
With the silk mill they prepared various types of yarns for wefts and warps.
The most famous of these was an organzino obtained from the twisted twist of two threads first twisted separately.
The historians of the industrial revolution claim that the silk mill in Bologna represents an important example of a protoindustrial factory system.
The production process was in fact fully mechanized, the workers were confined to feeding the machines, knotting the wires when they broke, removing the mats that were already twisted off the reel and put them in special baskets.
The length of the working day of mill workers was around 14 hours.
Because of a prejudice who considered sunlight damaging to the color of silk, worked in narrow spaces and in semi-darkness.
Closed air, damp, dusty and the excessive length of the working day, were particularly detrimental to the health of the workers, among whom there were numerous children.
Silk mill technology was kept in Bologna as the most jealous of the secrets because it was feared that spreading it to other cities would have fueled a dangerous competition.
However, despite the severe penalties for those who violated the secret already at the end of the 500, the spinning system was exported to Reggio Emilia and Venice.
Towards the second half of the 600, silk mill began to spread in the Lombardy and Piedmont areas.
At the beginning of the 700 an English industrial spy, John Lombe, carried the mill's secret to England and thanks to the help of specialized italian workers, he built a large silk mill near Derby.
According to some historians, this was the first modern factory in England.
For reasons of secrecy, the images we received regarding the silk machine are few, reticent or lacunous.
Only the drawings of Heinrich Schickhardt (1599) and Antonio Zonca (1607) reproduce the machine in its complexity, while not providing enough elements for construction.
Silk production has for centuries been the most important sector of economy in Bologna, guiding it was the powerful corporation named Arte della Seta.
Since the end of the 600's within the walls of Bologna, 119 silk mills were powered by 353 hydraulic wheels, the power of 1 or 2 hp, fed by the water that reached the cellars of isolated blocks.
The Bolognese settee, which at the end of the 16-th century gave life to about 40% of the population was divided into two areas:
White or veil work, which only employed local silk and the Tinted work, specializing in the production of organzine and drapes.
The farmers were obliged to sell raw silk on the urban market.
This is to feed the concentrated industries in Bologna.
Most of the silk produced was exported via Venice to the international market, in Flanders, France, Germany, England and the Turkish East.
Since the late 16th century, a slow decline in the Bologna silk industry began.
The construction of more refined mills able to provide the best quality products in Lombardy, Piedmont and Veneto; political instability, the wars of the Napoleonic period and the sharp decline in the production of cocoons coincided with the definitive sunset of the Bolognese silk industry.
Search curated by: Francesca Montevecchi and Agostino Tripald
CIS Department of Philosophy, University of Bologna