Wanlockhead Beam Engine

The date of construction and erection is not recorded, but probably occurred around the middle of the 19th c. This pumping engine, on Straitsteps Mine is the last remaining water bucket engine to be seen on a mine in the U.K. It is now owned and maintained by Historic Scotland.   The beam is made up of two baulks of pitch wood and is 7.4m long, 61cm deep and 28cm wide. Wrought iron straps bind the two baulks together and at the centre and ends are carved reinforcing pads. The beam is mounted on a pillar of dressed freestone 4.3m high and 2.1m x 91cm at the base.   The beam pivoted on a trunnion of ingenious design by which a massive wrought iron axle is jointed to a cast iron support under the beam centre. The axle turns in step plummer blocks on brass bearings and is anchored in the pillar by long tie rods which pass through the pillar and are secured at the base.   At the power end, the crosshead guiding the rod to which the bucket was attached moved inside a high wooden ‘steeple’. The bucket rod, fixed to the ‘steeple’ is 3.6m long and had a 23cm diameter plate at the bottom which supported the bucket.   The stone lined pit into which the bucket descended is 1.8m deep and in the bottom is a drainage outlet through which the water, when emptied from the bucket, flowed into the nearby burn.