Cragend Farm Hydraulic Silo

Cragend Farm Hydraulic Silo is an experimental hydraulic silo constructed between August 1884 and January 1887, commissioned by Lord Armstrong. The silo is located 45 metres east of Cragend Farmhouse (previously recorded as 70 metres east). Built of snecked stone with tooled-and-margined dressings, it has a Welsh slate roof to the centre, with original heavy corrugated iron on the side parts and a 20th-century asbestos roof to the loading bay. The linear design comprises two rectangular silage bays flanking a taller, cross-gabled central section.

The north elevation's gabled centre features boarded double doors and pitching doors above, both set within chamfered surrounds. The lower side parts have slit vents. A pent roof shelters the loading bay to the right of the elevation, accessed through a segmental arch with boarded double doors on the return side. The side parts have barrel roofs.

Internally, the central part houses a single-cylinder hydraulic engine in the basement (access currently unsafe), a turbine on the entrance level, and a first-floor chopping machine which has been removed. The flanking silage bays are deep, internally rendered chambers, with each containing 18 large stone drums on the floor. The structure incorporates transverse steel girders below the roof and steel arched roof trusses.

The silo’s design was reportedly influenced by a French original. Grass was forked in through the pitching door to the chopping machine, powered by the turbine below, which was in turn operated by water pumped up from the hydraulic engine. The chopped grass was manually loaded into the silage bays, compacted beneath the stone drums – which were raised to the transverse girders using hydraulic power – and then dropped down a chute to the low-level loading bay for removal via hydraulically operated hoists used to lift both silage and personnel.

The process proved inefficient due to the manpower required and was abandoned due to gas emanation problems. The power source was lost when Blackburn Lake was drained around 1930.