Читать книгу The History of Mining - Michael Coulson - Страница 46

Further to the west in what was then French influenced territory, the search for minerals uncovered lead deposits. In the 17th century French traders such as Louis Joliet and Robert de La Salle made journeys from Quebec which took them down the Mississippi River, eventually as far south as the Gulf of Mexico, and in the process the French traders observed outcropping lead ore which resulted in the opening up of the lead mines of the Mississippi Valley. These were amongst the earlier fully documented mining developments in what was to become the USA. The French explorer, Henri Joutel, recorded the existence of lead mines in the northwest part of Illinois in the late 17th century. It is also thought that local Indians had come across free lead and copper and not knowing how to work it had used it as adornment. With the coming of the French they soon picked up the idea of mining the lead ore and smelting it in hollowed-out tree stumps or in campfire hearths.

The reason for French interest in lead was its use as ammunition for the rifles of traders and trappers. One of the earlier Mississippi Valley lead mines was developed by Nicolas Perrot, a French explorer and trader, who was an important figure in the history of French colonies in North America as a diplomat working with the indigenous Red Indians. Perrot also had some knowledge of mining techniques and instructed Indian workers how to dig inclines into the orebody, thereby making it easier to set fires in order to fracture the ore and remove the richest material, a technique that should be very familiar to us by now.

Perrot was followed by Pierre le Sueur, another French explorer and trader, who had mistaken green sand for copper ore in an earlier loss-making deal. Le Sueur had hoped to further develop the lead mines in the area, including Perrot’s, but after initial work they were deemed to be uneconomic. Other lead mines, however, were developed by both the French and the English, including Mine la Motte in Missouri’s Ozark Hills. La Motte was eventually run by Philippe Renault, who came to America in 1719 and whose father was an iron founder back in France.

Mining in the Mississippi Valley was affected by Indian action from time to time, and for some decades lead mining was concentrated in Missouri, but by the end of the 18th century interest had returned to the region, including Illinois and Wisconsin. The treatment process remained fairly crude, using logs to shape a large fire and then melting the mined material in a large bowl within the structure. The resulting metal was then made into bars and often shipped to France.

Other French lead mine owners included Julien Dubuque, who operated in Iowa and Illinois and had a particularly close relationship with local Indians. Dubuque’s mines were thought to produce around 1000 tonnes of lead a year, enough with his winter trapping activities to make him a very rich man. His Indian miners operated in the traditional manner, again using fire setting to crack the ore and then stag horn implements to break off the metal bearing parts of the ore. Smelting was done in a log furnace but with a stone base, and built into sloping ground. Lead recovery was satisfactory at around 65%, taking into account the fairly rudimentary technology used. Mining by the French continued into the early decades of the 19th century and when the French began to leave the US, Indians took over the mines for a short period before the expansionary and now independent Americans from the east moved in.

The pace of exploitation accelerated as the US pushed west and more lead mines were opened. The Indians lost out and the expansionary US government began to enclose land and then issue leases to interested parties with royalty requirements attached. The system was on the chaotic side and not well policed initially by the government, but in due course mining became more organised, and more efficient smelting technology was introduced. The displaced Indians, indignant at losing their land, created problems and security remained an issue for many years. One of the worst offenders in his ignoring of both US government instructions and Indian rights was Henry Dodge, who in 1827 was producing at least 1.5 tonnes of lead a day from land owned by the Winnebago Indians in the Wisconsin Valley. Dodge, having made his fortune, became Governor of Wisconsin, a post he held for many years, and then became a US senator. However, by the middle of the 19th century a recognisable and organised lead mining industry was beginning to emerge, as we will discover later.