Steam power was once the prime source of power for most mines, providing energy for pumping, winding and transport.
When water is boiled in a sealed container, the steam produced cannot expand, so the pressure inside the container rises. This pressure can be used to push pistons or turn turbines to make machines work.
Cornwall played a leading role in the development of the steam engine, because this was the technology that was increasingly used to pump the deep wet mines.
Steam power was first adopted by metal mines during the second decade of the eighteenth century. This was probably at Wheal Vor between 1710 and 1714.