"At Ushaw Moor colliery, not far from Flass Hall, on the north side of the Dearness, is being worked the Busty seam, which contains a band which widens greatly to the west. The top coal is 1 foot 10 inches thick, and the bottom coal 3 feet 6 inches. A drift from this seam to Brockwell, 16 fathoms below, will shortly be opened to work that seam, which is about 3 feet 6 inches thick. This colliery was sunk about 1865, and when fully operating, employs over 500 men and boys. There are a large number of coke ovens, which convert about half the output into coke."

Whellan's 1894 Directory of County Durham via Durham Mining Museum