Cornish Beam Engine
This building with its great beam and rod reaching down into the ground houses some remarkable machinery.
In 1874, the Prestongrange Coal and Iron Company bought a second-hand steam-powered Cornish Beam Engine to tackle the problem of flooding. This machine had already worked at four different mines in the south west of England. It was dismantled and a new beam was cast then it was transported to Prestongrange by boat. It would play crucial role at Prestongrange.
Looking up at the end of the great beam, you can clearly read the name of its maker, Harvey and Company and the date it was cast.
Installation was no mean feat: the main engine weighed thirty tons. The engine house was built first and used to hoist the engine into place. If you move around to the rear of the building you might spot the archway which was one of the final pieces constructed after the great beam and carriage truss were winched into place. Although not noticeable from the outside, the front wall is nearly seven feet thick in order to withstand the stresses of the working machine. The Beam Engine was capable of pumping out 2960 litres of water a minute which works out at 4.5 million litres a day!
The engine eventually stopped running in 1954, just eight years before the colliery closed for good. Its job was taken over by electric pumps.
The Prestongrange Cornish Beam Engine is unique in Scotland as it is the only one still in place on the site it worked.