Threshing mill, 7 Legaterriff Road, Ballinderry Upper, Lisburn, Co Antrim, BT28 2EY

This water-powered threshing mill is located a short distance north of a block of farm outbuildings associated with The Grove (HB19/01/061A). It comprises a two-storey-over-basement, single-bay building aligned E-W at the bottom of a gentle slope down from the farmyard to its south. It measures 29ft 9in long x 22ft wide x 15ft high, with a 6ft 6in deep basement. Pitched natural slate roof (some ridge tiles and slates missing). Lime rendered rubble masonry walls with brick eaves course (render missing in places). No rainwater goods. Square-headed timber-sheeted doors in south and west elevations at ground floor level. The former is a half door and is set within a segmental brick head; this brickwork is a 20th century repair (cement-rich mortar). Basement lit by opening on W gable. Ground floor lit by openings on N and S walls. Top floor lit by opening in apex of W gable and by three small square openings along N and S elevations. All these openings were shuttered, but their frames are now missing. The E gable is devoid of openings. Directly above the door at the W end of the S elevation is a small recessed square datestone reading AD 1836, undoubtedly the date of the building’s construction. External high-breastshot waterwheel in middle of N elevation. Measures 12ft 0in diameter by 2ft 7½ in wide. Its axle, hubs and rims are of cast-iron; the latter are tied to one another with wrought-iron rods. Two sets of six timber arms, now mostly missing. The 36 angled buckets and soleplate were also of timber but have disintegrated as well. Cast-iron segment spur gear attached to inner arms. Drives cast-iron bull nut at 12 o’clock position, from which cast-iron axle runs into basement. Sluice gate directly above waterwheel missing. Mill pond directly behind E gable also infilled, as is headrace in vicinity of mill. Partly culverted tailrace still evident running W along side of lane to adjacent property. Projecting from the middle of the S elevation is a metal shaft. Its outer end is supported on a vertical metal post mounted on a rubble masonry base. It originally drove to a second shaft (now gone) which powered a woodworking lathe in an outbuilding directly south of the mill. Roof: Natural slate Walling: Lime rendered random rubble Windows: Timber shutters (missing) RWG: None