Beside the south-east gable, dropping into a wheel-pit just under one and a half metres wide, hangs a suspension overshot waterwheel of roughly seven metres in diameter. The axle is cast iron, the eight arms are wooden, and the buckets and shroud plate are larch, painted over with pitch to slow the rot. An overshot wheel is one where water is delivered from above, filling the buckets at the top and driving the wheel by weight rather than current, a more efficient arrangement than the simpler undershot type. That this one is still largely intact, inside a building that lost its roof long ago and now shelters under a corrugated iron lean-to, gives the place a quietly suspended quality, as though the machinery paused mid-turn and never quite resumed.

George Bolster built the mill in 1848, on the west bank of the Duvglasha River about one and a half kilometres south of Lombardstown in north Cork. The main structure is three storeys of random-rubble sandstone, roughly twelve metres long and seven metres wide, set into a north-east-facing slope in a way that allowed water to be brought from two separate sources. One millrace was drawn from the Glengarriff Stream, about one and a half kilometres to the west; a second was taken from the Duvglasha itself, at Lackavihoonig Bridge some five hundred and fifty metres to the south. Behind the mill, two stone piers once carried a launder, the wooden trough that channelled water from the millrace down onto the wheel, and part of the original sluice gate that regulated the flow still survives. A four-storey extension with brick-arched window openings was built against the south-west face, and a further two-storey, five-bay building attached to its west corner was converted into a residence in the early twentieth century. The mill itself had stopped working by the early 1930s, leaving behind its waterwheel, its stone walls, and the faint hydraulic logic of a site carefully engineered to draw water from two directions at once.