Magny shaft

Before 1873, the Ronchamp's coal mining company mined the central part of the Ronchamp and Champagney coalfields, but the shafts used for this purpose reached the end of their working life and had to be replaced. This was to be the role of the Magny shaft and the Chanois shaft, the sinking of which began at the same time in the southwestern part of the basin, separated from each other by a distance of 700 meters. The southeast part of the basin has been a disappointment, with the poor results of the Saint-Georges well and the premature abandonment of the Espérance and Saint-Jean wells, which have suffered from heavy water inflows and have therefore become too costly. == Sinking ==

Between 1856 and 1859, the Société civile des houillères de Ronchamp drilled the Pré de la Cloche borehole to the north of the future Magny shaft, revealing a layer 1.20 meters thick at a depth of 650 meters. At the same time, the competing company of the maîtres de forges was digging the puits de l'Ouest a few meters away, but this was abandoned after three meters. At the same time, the two companies were vying for the Éboulet concession, which was finally awarded to the Société des Maîtres de Forges in 1862. The two companies eventually merged in 1866. Sinking of the main shaft, circular in shape and bricked up, began south of the previous exploratory work in 1873. A 25-meter casing is sufficient to cross the aquifer zone, unlike the Chanois shaft, which is subject to heavy water inflows and is behind schedule. A second, smaller well was dug nearby, to serve as a relief and ventilation shaft. By June of the same year, the 3.50-meter-diameter main shaft had reached a depth of 180 meters, and the 2.20-meter-diameter relief shaft had reached a depth of 25 meters. On May 9, 1877, the shaft encountered a 1.20-meter-thick layer at a depth of 663 meters, along with two small benches of coal twenty and thirty centimeters thick. Five meters further down, another fifty-centimeter-thick coal bed was discovered: the intermediate layer. On October 20, 1877, the shaft reached the hard rock layer of the transitional terrain, without having encountered the second layer of coal, which was considered a bad sign by the engineers. In 1878, the sinking of the large shaft was completed. It reached a depth of 694 meters, while the small shaft reached 651 meters. == Surface installations ==

Numerous brick and stone buildings house the machines and various departments on the surface. The headframe is of the hangar type, i.e. made of wood and housed in a large masonry building. The extraction machine used for sinking the shaft comes from the Saint-Georges shaft and is therefore unsuitable for extracting 250 tonnes of coal in a ten-hour day. It was replaced by a more powerful machine requiring four boilers to turn it, two boilers for the fan, and a relay boiler. == Operation ==

When it was commissioned in 1878, the Magny shaft was considered a failure due to poor sinking results, but when the first extraction work was carried out, discoveries of good-quality layers over a meter thick finally ensured the shaft's future. He concludes that the accident was caused by the miner Pautot: having accidentally pierced his lamp with his pick, he climbs back up the inclined plane, hooks his lamp to the woodwork, and leaves with Peroz's. But he leaves his damaged lamp near a gas release, triggering an explosion. But he left his damaged lamp close to a gas release, triggering the explosion. Following this accident, the old Davy lamps were replaced by safer Mueseler lamps. In addition, a more powerful fan was installed the following year, to improve ventilation efficiency. This was a variable-effect SER system fan with a flow rate of 30 m3/s, compared with 10 m3/s previously. Finally, the company is blamed for the fact that the workings were ventilated downwards, rather than upwards as recommended. == Extraction ==

In the same year as the disaster, the Magny shaft took on additional importance compared to the company's other shafts, thanks to the installation of washing and screening workshops, the increase in the number of workers, which necessitated the construction of a coal preparation and washing room, and finally, the encounter, in the work to the east, of the second layer of coal measuring 4.20 meters thick. In 1897, the mining galleries had a total length of 12 km. By 1901, both strata were being mined to the north and south, with 26 cuts in operation. In 1908, a trench was dug between the Arthur-de-Buyer shaft and the Magny shaft. Service shafts The workings to the north and east (towards the old shafts) soon showed signs of exhaustion, and old mining operations, carried out from other abandoned shafts, were encountered as early as 1907. The Magny shaft remained the most productive, with production still exceeding 80,000 tonnes a year. In 1916, the decision was taken to abandon the Magny shaft as an extraction shaft, but it was retained as a service shaft for its two neighbors, the Chanois shaft and the Arthur-de-Buyer shaft. It continues to provide ventilation to the southeast shafts of the Arthur shaft. An airlock is installed at the shaft's mouth to avoid interfering with ventilation. A windlass is used to monitor the shaft column and lower firefighters and limbers to the bottom. The shaft entrance is equipped with an access hatch. For eleven years, the buildings were left untended and slowly deteriorated. New electric pumps were installed in 1932; two years later, a diesel locotractor replaced the horses for the 3.5 km drive. In 1939, the Canada bowette linking the Arthur-de-Buyer shaft to the Magny shaft was completed, and production from the latter fell to 1,700 tonnes from 2,500 tonnes three years earlier. By 1943, production was declining and no longer profitable; equipment that had broken down could not be repaired for lack of spare parts. The well's reserves were estimated at 288,000 tonnes. Work continued intermittently until the end of the Ronchamp colliery's life. Work was interrupted in 1940 for more than a month, and again in 1944 to restore the installations after the Liberation. By 1945, the company was planning to shut down the shaft. When the French coal industry was nationalized in 1946, at the instigation of the provisional government led initially by Charles de Gaulle, the Ronchamp coalfield was entrusted to Électricité de France (EDF), as it was too far from other major coalfields and included a major thermal power plant. The following year, the shaft still employed 38 people, including a dozen miners. EDF stopped exploration work in 1950. The following year, the shaft was shut down again, while the Chanois shaft closed for good. To prevent water from the Chanois from invading the Magny, a watertight plug was installed at the entrance to the gallery linking the two shafts, and a 40 cm ring of concrete was poured around the gallery where it opened to withstand the pressure of the water. Mining resumed in 1953 to exploit the Clovis panel (a part of the mine that remained undeveloped). It was from this panel that Ronchamp's last coal sedan was extracted on Saturday, May 3, 1958. At the beginning of the 21st century, the old administrative building dating from 1927, the old boiler building, the ruins of the large extraction building and the overgrown changing rooms, and two pieces of wall from the storage building remain. Few traces remain of this mining operation, which lasted almost 80 years. File:2015-03 - Puits du Magny 52.JPG|General view of the Magny well from the Ronchamp-Clairegoutte road. In the foreground, is the white-painted boiler house, now converted into housing. File:2015-03 - Puits du Magny 02.JPG|Scattered pieces of wall. File:2015-03 - Puits du Magny 42.JPG|Remains of a wall near the ruins. File:2016-06 - Puits du Magny - 09.jpg File:2015-03 - Puits du Magny 08.JPG File:2015-03 - Puits du Magny 34.JPG File:2015-03 - Puits du Magny 32.JPG File:2015-03 - Puits du Magny 43.JPG File:2015-03 - Puits du Magny 10.JPG File:2015-03 - Puits du Magny 25.JPG == The city ==

To accommodate the first single Polish immigrants arriving in Ronchamp between the wars, a large temporary dormitory was built on the pit floor. When the housing estate was built, it was converted into apartments and a canteen to accommodate families. The Magny mining estate was built in 1929 and is divided into two parts. The first part is located along the Clairegoutte road towards Ronchamp, while the second is built between the pit floor and a pond. This mining settlement can accommodate up to 300 miners. After its closure, the Magny well gave its name to this mining settlement, which became a hamlet attached to the village of Magny-Danigon under the name “Le Puits du Magny ”. The hamlet has no direct road links with the commune, and is served by the D 4 or Route de Clairegoutte, which links Ronchamp and Clairegoutte. File:Cité minière du Magny.JPG|General view of the Magny mining town. File:Puits-du-Magny-2013 (26).JPG|The mining town seen from the south. File:Puits-du-Magny-2013 (25).JPG|The artificial pond that powered the well's steam engines. == The slag heap ==

The Magny pit has a fairly long, flat slag heap extending as far as the Cenci sawmill, where a small bridge over the Beuveroux stream still stands at the beginning of the 21st century. The slag heap is colonized by birch trees. File:Puits du Magny 12-2013 01.JPG|The Magny well slag heap. File:Puits du Magny 12-2013 02.JPG|Another view of the slag heap. File:Puits du Magny 12-2013 03.JPG|The Beuveroux bridge. File:Puits du Magny 12-2013 04.JPG|Another view of the bridge. == See also ==