Convent of Mercy, Thornhill, Culmore Road, Londonderry, BT48 8JF

Thornhill is a large, substantial Victorian villa built in 1882 in a severe, almost harsh Scottish Baronial style with Tudor influences. It was designed by the architects Turner and Babington and constructed in snecked sandstone quarried at Dungiven. The house was built as the private residence of Andrew Alexander Watt, one of the most prosperous merchants in the City of Derry, and stands magnificently sited on the west bank of the River Foyle where it flows between Rosses Bay and Culmore. It is now in use as a religious house, owned by the Convent of Mercy.

EXTERIOR

The house is a large, two-storey stone building with attics and a basement. Its roofline is broken by many stepped gables of varying sizes, steeply pitched natural slate roofs and tall ashlar chimneys rising well above the ridge. The chimneys are built with rounded narrow sides, moulded bands and caps. There are no roof overhangs; a simple plain string course runs beneath cast iron gutters with matching rectangular downpipes and trunkheads where required. Two two-light dormers with square heads sit on the higher roof.

The west elevation forms the main entrance front, approximately eight or nine bays wide. A central square projecting bay, one storey high, contains a recessed arched opening with a comparatively small square-headed door. This entrance sits at the end of a higher ridged section that thrusts forward; at the opposite end is another projecting single-storey bay, also with a flat roof. Behind these two projecting bays, two narrow stepped gables break the roofline, the one behind the entrance rising a further storey. Windows throughout are generally narrow and tall, arranged in groups of two or three and occasionally as singles, divided by stone transoms and mullions. Over the entrance bay, coupled windows are capped with angular pediments; over the other projecting bay, a segmented pediment. This block, which is three rooms deep, contains the principal spaces.

To the north of the entrance and set back from it is a lower two-storey wing terminating in the kitchen, which has its own separate entrances. The kitchen wing projects forward with a crow-stepped gable; its round-headed entrance has a lean-to roof. Windows in this wing are again a mixture of singles, doubles and triplets, with two round-headed singles at first floor level abutting the higher block. Above these is a pleasing oculus — one of the few ornamental refinements in the overall composition. The kitchen windows themselves are wider and taller than those elsewhere on the house and are divided into five panes, comparable in character to those in the associated stable block. The north elevation of the kitchen wing is three bays long with a double-pitched projecting porch at the north-east end. This porch has a crow-stepped gable with a pair of round-headed windows and a centrally placed oculus above. The windows on this elevation are irregularly spaced and square-headed, with sliding sashes at first floor level. To one side of the projecting porch, steps lead down to a basement doorway. The steep pitched roof carries three two-light dormers.

The east elevation displays a degree of symmetry in the composition of the main block, which thrusts boldly forward from the service wing. It is five bays long with stepped gables at each end projecting forward, and between them a veranda with a curved metal roof supported on slender cast iron columns. A central polygonal bay pushes up through the veranda roof and terminates in a steeply sloped pyramid roof. The end bays each have large square windows at ground and first floor, subdivided by sandstone mullions and transoms. The intermediate windows are two-light and similarly divided at first floor level, while at ground floor they become French windows. One bay of the veranda is open; the other two have decorative metal balustrading. The service wing on this elevation has a mixture of square and round-headed windows; a group of three windows lights the service staircase and expresses its semicircular flights. The main block gable has irregularly spaced two-light windows, and the return walls of the projecting bays are punctuated with single-light square-headed openings. In keeping with the pattern elsewhere, each stepped gable typically features a slender round-headed window, though one gable has unfortunately had a recent square window inserted.

The south elevation has been altered since the addition of the convent chapel in the 1960s. It otherwise follows the pattern of the other elevations, with a mixture of square and round-headed windows, and a rectangular bay at ground floor on the west gable. A contemporary narrow conservatory abuts the connecting porch to the chapel. Originally the site had a curved glass roof conservatory in this position, as seen in photographs dating from around 1920.

All windows are timber, painted white.

HISTORY AND OWNERSHIP

A long, low building existed on this site in the 18th century and was subsequently enlarged to an L-shaped plan, as recorded on the Ordnance Survey map of 1832. That map also shows the site landscaped with a double avenue approach. The Ordnance Survey Memoir records a William Leathem in residence and notes that the Thornhill property belonged to Captain Hart. The Griffith Valuation of 1856 records a Reverend H. Scott as lessee at a valuation of £23 0s 0d, with Leathem as lessor. Later in the 19th century the property was acquired by the Watt family, and building of the present house began in 1882.

Andrew Alexander Watt was the owner of distilleries in Abbey Street and Waterside, Derry. The Abbey Street distillery was acquired by the Watt family in 1826 and greatly enlarged thereafter, achieving an output of 1,260,000 gallons of Patent Grain Whisky in 1887. The Waterside distillery produced Old Pot Still Whisky. Watt took little active interest in politics but was much engaged in the social life of the city and kept well-equipped stables and horses. The distilleries closed in the 1920s, and the Sisters of Mercy acquired Thornhill in 1928. A college for girls was established in the house in 1932, with boarding pupils occupying the attics, which were converted to dormitories. The nuns made little change to the fabric of the house; chimney pieces, mouldings, and the disposition of windows and doors have remained relatively unchanged. In 1998 the entire premises were renovated, leaving both exterior and interior in very good order. The 1998 renovation was carried out by the architects Loughrey and Agnew.

SETTING AND GROUNDS

Thornhill occupies a magnificent site on the west bank of the River Foyle, set on sloping ground elevated well above the river, with panoramic views of the surrounding landscape. The grounds are well laid out with mature trees set in lawns. From the veranda, steps lead down to a formal path that dips towards the river. To the side of this path is a cemetery for deceased members of the Sisters of Mercy community. A winding avenue sweeps in from the Culmore Road, passing the former walled garden, which is presently in use as a commercial nursery. The generous landscaped gardens form an essential part of the character and ambience of the house.