BALDHU, an ecclesiastical parish, in the parishes of Kenwyn and Kea, union of Truro, W. division of the hundred of Powder and of the county of Cornwall, 3½ miles (S. W. by W.) from Truro. This place derives its name from Bal-mine-dhu, or rather diu, black; it is about three miles in length and two and a half in breadth, and of hilly and barren surface. The Carnon river forms its boundary on the south, and the Truro and Redruth road on the north; the Cornwall railway passes nearly along its boundary on the east. Several mines are wrought, the chief produce of which is black-jack and black tin. The "Old Men's Workings" consist of gigantic excavations in the Elvan rock, open to the sun, in some places more than 150 feet deep, and extending a distance of a mile and upwards: they are probably among the original mines of the county, and are not now wrought. There are also several smelting-houses. The parish was formed in 1847, under the act 6 and 7 Victoria, cap. 37; the living is in the gift of the Crown and the Bishop of Exeter alternately, and has an income of £150. The church was erected in 1847-8, at a cost of £1800, of which sum the Earl of Falmouth, who had the first presentation, contributed £1000; the Incorporated Society, £200; the Diocesan Society, £250; and the Church Commissioners, £260.