The States of the Church developed a strongself-sufficient mining, metallurgical and armamentpolicy since the end of the Middle Ages. The financialsupport was given by the Reverend Apostolic Camera( RCA ) to carry out firms and plants let to privatecitizens with forward contracts. Two main trails we re followed.The first consisted in the treatment of the importedElba ore in blast furnaces located on the coast of theThyrrenian sea, such as those in Conca (for theeconomical support to the Holy Office), Canino orBracciano, with a following finery process in forgeslocated in the same place (Conca and Campoleone) ornearby (Ronciglione - Canino).The second looked at the exploitation of local mines,which actually resulted neither abundant nor rich toobtain suitable results. Both mainly consisted in theso-called brescian furnace technology, which treatedthe ore with an indirect process.The brescian furnace was well developed since the 15thcentury and spread all over the peninsula by familiesfrom Brescia and Bergamo, holder of secrets of buildingand running such plant. This blast furnace, also knownas canicchio, was blown either by bellows or by atypical italian machine, the hydro-aeolian trompe,which supplied compressed air compelled into a fallingjet of water without any moving mechanism. Thecanicchio, bi-pyramidal in shape and 4-7 m high, wascharged with ore and charcoal from the top and showedmainly frontal access for blowing and tapping. The highconsumption of charcoal and water needed a location close to these sources.This work deals with the history of iron ore resourcesexploitation along the Valnerina "trail" in the 17th and 18th century.The first incident is located in Monte Leone di Spoleto,where iron ores, found (or re-found) in 1629, seemedsuitable to produce armours and harquebuses. In about1640 a charcoal-fuelled bellow-powered blast furnaceis proved to produce pig iron on the bank of Corno riverA finery was built in the village of Scheggino, and anew road connected the mines and the furnace to the main road (Flaminia).It's a great event, the Pope Urban VIII who stronglywanted the ironworks decided to celebrate, striking themedal of his 18th year of papacy with a view of the activities.The medal shows a portrait of Urban VIII. In the reverseminers and metallurgists at work are framed by a garland(where is possible to distinguish among the leaves thebees of the Barberini's coat of arms, the family of thePope) and the legend FERRI FODINIS APERTIS (for theopening of iron mines) ROMA MDCX)CtlCIl (1642). Theyear is the same of the death of Galileo (January, 8th),is the same also the Pope of the process and abjuration (June 22nd, 1633).All this area was de-vastated by earthquakes in 1703;the Corno river flow changed, cutting off the hydraulicpower. The curtain falls for the first time on the Monte Leone plants.The iron ores of Stifone were found in 1708 andexploited in about 1710. A few years later all was readyfor pig-iron production. Different overshotwaterwheels provided the power to couples of bellowsand to the hammers. The sections of the canicchioclearly indicate a bi-pyramidal shape, with verticalfront and back sides. This plant too lived a wretchedlife; the shortage of local ores suggested in 1736 tostock up on Elba ore, but the distance from the sea madethe task not economically viable.A second try in Monte Leone was urged after the recoveryof the water flow of the river Hoping in a discoveryof more abundant veins, in 179] the RCA charged theengineer Gian Gualberto Gnema (born iii Valsesia,Piemonte) to build a little furnace to test the ironore. Following the initial success of such experiments,an higher canicchio blast furnace was quickly built onthe ruins of the former furnace. In the summer 1792 amean daily production of 915 kg/d pig iron was reachedand mainly used for casting cannonballs. In Novemberthe floods of the river damaged both the dam and theducts: once again the business was unsuccessful!After the repairs
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