Mining Methods
Lead had traditionally been found by following veins from surface outcroppings, particularly in "rakes" or vertical fissures. By the 17th century, however, most surface lead had been mined and prospecting was achieved by less direct methods. Miners searched for surface signs that were similar to known lead-rich areas, they checked ploughed and other disturbed land for traces of ore, and they checked for signs in plants and trees and poorly performing crops, since lead is poisonous to most living things. They used probes to check for signs of ore in soil a few feet under the surface and dug exploratory holes or trenches in promising places. This was usually done to choose the best places to sink shafts ahead of existing working and the rules defined when and where these activities could be carried out.
The miners sank their shafts in turns of up to 90 feet (27 metres), each turn being a few yards away from the bottom of the preceding one, along a gallery which may have been the working level reached by the earlier shaft. They climbed up and down their shafts using either footholes in the shaft walls or stemples, wooden steps built into the sides, an exhausting and dangerous way to start and finish a day's work. These climbing shafts were usually within the miners' “coe”, the limestone-walled cabin in which they stored tools, a change of clothes and food. Where the mine was on a hillside the vein could often be reached via an adit or tunnel driven into the slope.
Ore was brought to the surface up a winding shaft outside the coe. The miners' equipment included picks, hammers and wedges to split the rock, wiskets or baskets to contain it, corves or sledges to drag it to the shaft bottom, and windlasses or stows, to lift it to the surface. In later years underground transport was improved by replacing corves by wagons, often running on wooden or metal rails. A good example of an 18th-century wooden railway can be found in the Merry Tom mine, near Via Gellia. The miners avoided the need to excavate hard rock whenever they could and where it was unavoidable sometimes resorted to fire-setting. A fire was built against the rock face after mining had finished for the day and allowed to burn through the night. Fragmentation of the heated rock was increased by throwing water on to it. The rule about fire-setting only after the end of the day's work was important because in the confined mines the smoke was deadly. Fire-setting was a skilled technique and was used sparingly for that reason as well as because of the disruption caused by the smoke and the danger from splintering rock.
Read more about this topic: Derbyshire Lead Mining History
Famous quotes containing the words mining and/or methods:
“Its a mining town in lotus land.”
—F. Scott Fitzgerald (18961940)
“The comparison between Coleridge and Johnson is obvious in so far as each held sway chiefly by the power of his tongue. The difference between their methods is so marked that it is tempting, but also unnecessary, to judge one to be inferior to the other. Johnson was robust, combative, and concrete; Coleridge was the opposite. The contrast was perhaps in his mind when he said of Johnson: his bow-wow manner must have had a good deal to do with the effect produced.”
—Virginia Woolf (18821941)