Le Bocard trail

10 points of interest

• 

  

  History

  We’re recruiting!

  In the 19th century, miners had an advantage over farmers: they were paid their wages directly. Like other companies at the time, the factory in Vialas had developed paternalistic policies that led its staff to abandon farming and become proletarianised. At its height, in 1866, the factory had 522 employees spread over several sites. The company’s difficulties from the late 19th century onwards had demographic repercussions on the municipality, which lost almost 40% of its population in about 50 years, with most probably migrating to the mining basin of Alès.

• 

  

  Geology

  The good filon

  All rocks are minerals but some are considered ores because they contain a metal or precious substance. As soon as the mineral is mined for the metal it contains, it is called an ore. Galena is an ore found in seams; it contains lead. However, it was not lead that was mined in Vialas, but silver: when the seams formed, a substitution of atoms occurred which produced lead ore containing silver: argentiferous galena.

• 

  

  Know-how

  Let’s start mining!

  When the ore seams were discovered in 1781, nobody remembered any previous mining in Vialas. And yet, according to the mine director at the time, some tunnels showed signs of having been mined using fire. This technique, known since prehistory, consists of heating the rock face to make the rock shatter. This is supposedly why one of the seams is called “ancestors’ seam”. We do not have sufficient evidence today to determine definitively whether or not there was mining here before the 18th century.

• 

  

  Know-how

  The pithead

  At the exits of the mine’s main tunnels were several areas and corridors for sorting the ore, such as these.

• 

  

  Architecture

  How the factory was organised

  The factory is below you. It gained the name of Le Bocard from one of the particularly noisy machines which crushed the ore. Opposite you, many workshops for mechanical processing have been destroyed. These buildings also provided lodgings for staff on the first floor, and were arranged so as to take advantage of the water supply. Water was the main driving force of the factory’s machinery, which meant that periods of drought or frost were very disruptive.

• 

  

  Know-how

  Mechanical processing

  This operation removed as much sterile rock as possible, keeping only the rock richest in ore that was ready for smelting (called schlich). Several machines were used at various times to crush and then categorise the ore by size and density: the higher the ore content, the heavier the rock.

• 

  

  Know-how

  Getting hot!

  The foundry was established in 1827, before being modified and extended in 1860. The schlich arrived at the foundry for metallurgical processes, which were the final step to obtaining pure silver. First the metal – meaning the argentiferous lead – had to be separated from the galena. This was done by roasting and then smelting it in a reverbatory furnace. This produced lead containing silver, called lead bullion. The lead then had to be progressively separated from the silver it contained, using cupellation. In 1847, Vialas produced one-quarter of France’s silver.

• 

  

  Know-how

  Going up in smoke

  Smoke was emitted as far as possible from the factory. But it contained lead and silver particles, which were collected using the sack-like filters that you can see in the corner of the stack, by the side of the path. These “sacks” trapped the silver and lead particles, which were heavier than the other components of the smoke. The silver was transported to Paris by stagecoach, the lead and other products by cart and then by train to Beaucaire.

• 

  

  Architecture

  Cover everything !

  There was not enough space available in the valley for the factory. To save space, the factory was given a vaulted ceiling, which created a flat area. Consisting of several sections and built from small slate blocks, the vault covers La Picadière brook for almost 100m. The brook was not used to drive the machines, its flow being too irregular. Instead, the Luech river was partly diverted to supply the factory.

• 

  

  History

  Sleeping Beauty mine

  This is a green hollow and the literary inspiration for the first chapter of Jean-Pierre Chabrol’s novel La Gueuse, which is entitled “The Sleeping Beauty Mine”. The association Le Filon des Anciens maintains the site, cutting back brambles and revealing forgotten elements, such as the canal that used to carry the river water, which you will spot below the path by the factory. Regular maintenance of the site preserves this exceptional heritage and may uncover further elements.