Fahrkunst

A man engine is a mechanism of reciprocating ladders and stationary platforms installed in mines to assist the miners' journeys to and from the working levels. It was invented in Germany in the 19th century and was a prominent feature of tin and copper mines in Cornwall until the beginning of the twentieth century.

Operation

In the Cornish examples the motive power was provided by waterwheels, or one of the mine's steam engines. The steam engine or water wheel would be linked to a series of beams – known as "rods" – fastened together and reaching to the bottom of the mineshaft. These were arranged to offer a reciprocating motion of, typically, twelve to fifteen feet (three to five metres). Small foot platforms were attached to the rods at the same distance apart as the engine stroke and fixed platforms ("sollars") were built onto the shaft walls, spaced to coincide with the top and bottom positions of each of the moving platforms. The moving platforms were often small, typically square, to make the miner stand close to the centre-line of the rod and thus keep a safe distance from the sides of the shaft. For the same reason the grab handles were always fitted directly above the foot platforms. To go up or down, the miner would step onto the travelling platform and allow himself to be carried to the next fixed platform, where he would step off and wait. At the end of the next stroke the next moving platform would line up and he could step onto it and repeat the process. Miners could ascend and descend at the same time: the pause at the changeover point was made long enough (typically between two and eight seconds) for two men to change places. To facilitate this some installations (such as at the Devon Great Consols mine, Tavistock) had a fixed platform at both sides of the shaft, one side for miners descending and one for those on the ascent. Counterweights – large boxes filled with stones attached through "see-sawing" horizontal beams – were installed to avoid the full weight of the shaft and men bearing on the top linkage. In the deepest mines, which could sink to more than 350 fathoms (640 metres), extra counterweights were provided at regular intervals, in horizontal side galleries.

In a common variation a pair of rods was used, with one on its upstroke as the other descended. The miner hopped from one to the other, rather than waiting at a fixed rest, as they changed direction.

Rotary steam engines were found to be more suitable than beam engines because the steady speed of the heavy flywheel gave a predictable pause between reversals of direction, whereas pistons acting directly on the rods, even when controlled by a cataract governor, could surprise the passenger by irregular waits, longer or shorter. In Cornwall only the Wheal Reeth man engine, Godolphin, (where a pumping engine was converted to this new use) was powered by a piston acting directly on the rods. When not in use for the man engine, it was an advantage that a rotary engine could also be used to power a whim.

History

The earliest known examples of this device were from the first half of the nineteenth century in the silver mining area of the Harz mountains, Germany, where they were driven by cranks connected to water wheels, although bucket hoists ("Hakenkunst") using the same method of operation had been used in Swedish iron mines since the 17th century. They appear to have evolved from an informal modification to the beam pumps, where the miners used spikes stuck into the wooden pump rods to get themselves carried up the shaft. As beam pumps were universal in deep mines, it was a then simple development to make proper platforms to carry the miners. The first formal engine was installed in 1833 at a mine at Clausthal, Lower Saxony, where inspector Wilhelm Albert and manager Georg Dörell fastened foot platforms and hand-holds to adjacent, reciprocating pump rods, using a waterwheel-driven pump put out of use when a new drainage adit was made at a lower level. The 1837 man engine at the Samson Pit

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