I found this just starting my research on this couple:
THOMASTOWN, a village in the parish of RELICKMURRY, barony of CLANWILLIAM, county of TIPPERARY, and province of MUNSTER, 4 ½ miles (W.) from Cashel, on the road to Tipperary, and near the river Suir: the population is returned with the parish. Thomastown House, the splendid castellated mansion of Lady Eliz. Matthew, sister and heir of the late Earl of Llandaff, is situated in a noble demesne, comprising upwards of 2000 statute acres, and embellished with a profusion of remarkably fine timber, and two large pieces of water, supplied from a distance of several miles: the scenery is of a very pleasing character, the fine range of hills called the Galtees forming the background. On a part of the demesne called the Ross, near the small river Fidachta, is a beautiful cottage, built by the late Earl. A constabulary police force is stationed in the village; and there is a school for children of both sexes, in which are about 100 children, under the patronage of Lady E. Matthew, who allows the master £10 per ann., besides a house and two acres of land. Some remains of the church exist; it is the burial-place of the noble family of Matthew.