The careful joinery, the mortices cut to receive and lock other timbers together, pointed to something purposeful rather than accidental. These were not driftwood or flood debris. They were, most likely, the surviving remnants of a horizontal mill.

A horizontal mill, sometimes called a tide mill or Norse mill depending on context, is one of the earliest forms of water-powered grain milling. In the Irish variety, water was channelled down a chute to strike a horizontal wheel fixed directly to a vertical shaft, which in turn rotated the upper millstone without the need for gearing. The technology was widespread in early medieval Ireland, and dozens of examples have been identified through waterlogged timbers preserved in streambeds and bogs. The stream at Cloghbally flows northwest to southeast, and the position of the beams on the downhill run of a fast-flowing channel is consistent with the siting logic of such a mill. The landowner noted additional timbers at the same location, suggesting that more of the structure may survive beneath the water and silt. Alongside the mill evidence, local tradition identifies an old road aligned east to west, crossing the stream just to the south of the find-spot, hinting at a small node of activity, a crossing point, a mill, perhaps a settlement, that has otherwise left no trace above ground.