Leather buckets and manpower were used to drain these early mines.
Where the terrain permitted, gently sloping tunnels known as adits were dug to remove the water from the hills to the valleys or from the coastal mines to the sea, often powering mine machinery further down their path.
Although buckets, waterwheels and adits had been successfully used for many centuries, removing the water out of the mines was a constant problem as mines got deeper. The introduction of steam power revolutionized mining as it vastly improved the amount of water that could be pumped out, allowing miners to reach much greater depths.
The Wheal Hermon Pump
Wheal Hermon is one of the oldest recorded mines in the area and was working in 1560. In 2001, heavy seas moved boulders on the beach at Penanwell, near St. Just, where the adit or drainage tunnel emerges. A section of timber pipe was discovered by Geoff Treseder of the St. Just Mines Research Group.
The artefact was examined and subsequently excavated by archaeologists from the County Council Historic Environment Unit. It has been radio carbon dated: it was made in the period between 1510 and 1560. With the co-operation of the National Trust, the owners of the site, conservation work was carried out by the York Archaeological Trust.
The pipe proved on examination to be a pump column. It is made from elm wood and has a wrought iron band around one end. It is remarkably similar to the illustrations in the book ‘De Re Metallica’ written by the German mining engineer Agricola in 1556. This was the first textbook about mining and shows the technology being used in the south of Germany in the 16th century, where waterwheel driven pumps represented the cutting edge technology of the day. Pumps enabled men to work below the natural water level in a mine. At Hermon, this meant working below sea level. The tin lodes can still be traced in the rocks at low tide across the beach.
We now know that by the mid 16th century, Cornish miners were using the most advanced technology in the world to win the increasingly valuable tin reserves. Like all mine sites, archaeological work at Hermon is made complicated by later mining operations. We know that there were periodic attempts to rework the mine between 1785 and 1927. The adit where the pump was found was reopened in 1912 and efforts to work the mine continued until 1972. In one of the reworkings – probably the 1912 attempt – pipes were installed to take water from the adit. It is likely that the pump column was reused as a waterpipe and installed in the adit, held in place by stone revetments which can still be seen.
This very rare survival has helped us understand the first attempts to mine beneath the sea – which continued at Geevor until 1990.
Photograph reproduced with the kind permission of the Geevor Archive