Название: The History of Mining
Автор: Michael Coulson
Издательство: Ingram
Жанр: Зарубежная деловая литература
isbn: 9780857192660
isbn:
Mining has never been a natural activity for the French, who are far more comfortable with the agrarian way of life, and in the 13th and 14th centuries the mines found themselves the target of rising rental claims from the landowning nobles who were often at odds with one another, inserting another layer of uncertainty for the mines. The mines also had to battle against rising operating and labour costs, the latter being particularly affected by an end to the system of forced labour.
The Paris Basin
Perhaps in hindsight one of the strangest mining areas in Europe was the Paris Basin, where a considerable number of mines were developed in the Middle Ages in the area of what is now substantially the city of Paris. The minerals won from these mines were not the glamorous ones of gold, silver and copper but were industrial minerals such as gypsum and building stone for Paris’s expansion. Indeed, it is the gypsum deposits of Montmartre that gave the name to the well known product plaster of Paris, and mining of that gypsum was first recorded in the late 14th century. In the 13th and 14th centuries stone quarries were developed well away from the old city centre and they were often accessed by digging a large shaft down and then mining the stone horizontally. This continued until the 15th century when the city began to expand towards these previously mined and now forgotten areas.
As the decades went by major buildings such as the Observatory and the Val de Grace church in the south of Paris were built on top of the old quarries and mines, as were a number of roads going south towards Fontainebleau and Versailles. In time cave-ins occurred, sometimes with considerable loss of life, and in the end the City had to survey the old mine workings, map them and secure them. The underground mines of Paris are sometimes referred to as the Catacombs, and though most of them are legally off limits today not everyone pays attention; unofficial visitors to them are known as cataphiles.
5. Great Britain
Until the 20th century Great Britain was a major producer of metals. Initially, in the Middle Ages, it was an exporter, but it turned consumer as the Industrial Revolution broke and then finally it became a major importer in its role as the world’s leading industrial power. In the Middle Ages England was on the edge of Europe, a feisty independent country with an historical relationship with France going back to the Norman Conquest, in the aftermath of which Britain inherited power over huge swathes of France which it gradually lost.
In due course continental powers like Spain, Holland and France came into conflict with England, which due to its powerful navy was becoming increasingly outward looking, a match militarily for anyone wanting to make trouble, and confident enough to start expanding its global reach through land acquisition and eventually colonisation. This latter development was a key part of the economic imperative to find natural resources to fuel the Industrial Revolution.
The importance of silver in the Middle Ages in its role as specie or coin led to a surge in silver mining, as we have observed earlier. England as an historic source of the metal became a serious producer based on the revival of its past operations in the southwest and new mines developed further north. Following the Norman Conquest in 1066 England’s silver mining industry was to be found in Somerset’s Mendip Hills, the Derbyshire Peak District, on the Welsh borders and in the North Pennines, which was the location of the most productive mines.
The ownership structure, which had been based for centuries on who owned the land where the silver was found, changed during the 13th century when the Crown claimed control of the silver, and therefore of the mines being developed in Devon at the end of that century. In this still feudal era there were also surprising examples of self-employed miners who leased mines, which they worked for personal returns. In the earlier part of the Middle Ages the mines were in the main small hand dug pits, but as we have seen elsewhere the veins often plunged and so shafts had to be sunk to follow the mineralisation. These shafts were sunk to the level of the water table where the miners had to de-water by hand. In due course rising silver prices on the continent financed the development of mechanised de-watering systems in the late 15th century, often using wheel and bucket lifting methods. There was also an environmental cost to the re-opening of the silver mines of south Devon, namely the stripping of woodland for fuel to be used in the treatment process and to provide mine timbers.
Silver and lead mining continued off and on in Devon well into the 18th century, as did mining in the North Pennines, and new mines were also established in mid-Wales. By the end of the 18th century mining had begun to extend below the water table in Devon as technological advances led to the development of steam-powered pumps capable of greatly exceeding the pumping rate of traditional bucket de-watering methods.
As far as treatment processes were concerned, new smelting techniques gave rise to changing fuel types, from traditional charcoal, on to peat where available, and then later in the 19th century coal, helped by advances in smelting technology, became the prime fuel. This also led to the development of treatment complexes close to the expanding coalfields.
6. Spain
Whilst the Spanish were involved in acquiring gold from their South American conquests, at home mining of gold continued along with the mining of other minerals, largely from historic mining districts, some of which had been active for several thousand years. Permission to mine coal in the Seville region at Villeneuva del Rio was given by the Crown in 1621. Initially individual miners worked the coal seams but in 1740 the Royal Artillery Petty Officers of Seville took over the mines as rising industrialisation and therefore rising demand led to a need for more integrated and efficient mining practices. After further changes of control in the 19th century, the mines were nationalised in 1969.
The iron ore mines of Viscaya in the north at Las Encartaciones were worked throughout the Middle Ages, as were the iron ore deposits of the Valle del Sabero in Leon in the north. The gold mines at Rodalquila in Almeria and the iron mines of Ojos Negros in Aragon were other ancient operations which were mined right through from the medieval period to the modern era, as were the Almaden mercury deposits in Castile-la Mancha, the salt mines of Iman in Guadalajara, and the coal mines of the Valle de Sabero in Leon. Many of these areas crop up again later when the Industrial Revolution led to a surge in demand for minerals throughout Europe.
Particularly unusual was the Almadèn mercury mine, which is believed to have operated for an unbroken two millennia, although there is a view that it may have been exploited as long ago as the 6th millennium BC. The deposit contained cinnabar, from which liquid mercury was produced by a reduction process. The first recorded reference to Almadèn was in the 5th century BC, and during the Roman occupation of Spain the mines were extensively exploited. With the fall of the Roman Empire there was no further reference to mercury mining in Spain until 711, when the Arabs overran the country and operated the mines until their departure in the 12th century. The mine then came under the control of the Spanish Crown. In ancient times mercury was used as an elixir of life and even as a treatment for broken bones, later it was used as an ointment and in cosmetics. These are all uses that, bearing in mind the great toxicity of the metal, seem curious to modern minds.
The conquest by Spain of Latin America in the 16th and 17th centuries led to a massive boost in Almadèn’s fortunes as the discovery of particularly silver, but also gold, deposits led to a major increase in demand for mercury as an amalgam to separate precious metals from their ore. Although presenting grave health risks to workers who operated the treatment process, the demand for Almadèn’s mercury in Spain’s New World colonies rose materially. By the 18th century, local mercury was being used to treat Latin American СКАЧАТЬ