The finished iron is produced from local pig iron, and from pig iron brought from Derbyshire, Yorkshire, and North Staffordshire. The steel production in South Staffordshire is gradually increasing. The processes adopted are those known as the Bessemer, Gilchrist and open hearth.

The South Staffordshire fireclay is worked principally in the neighbourhood of Brettle Lane and Stourbridge, and is employed in the production of firebricks, gas retorts, pottery, etc. Much also is conveyed into other districts in a raw condition for pottery purposes.

The Silurian limestone is worked partly in open work in the neighbourhood of Dudley, and partly by ordinary underground mining operations at the Wren’s Nest, Sedgley, and at Walsall.

Characteristic Features of the Mining of South Staffordshire.—There are several noteworthy features in the mining of South Staffordshire. A stranger is especially impressed with the large number of separate collieries in working (about 600) in proportion to the quantity of mineral raised. This peculiarity is due essentially to the insignificant depth at which the minerals occur below the surface (indeed, at Foxyard, near Tipton, coal has long been quarried in an outcrop of the 10 yard seam). This “Shallow Mining” has passed its meridian. The future mining of the district is forecast by those remarkable operations on the “red ground,” forming the eastern side of the coalfield. The most recently opened seam in the red ground is at Hampstead, three miles north of Birmingham, where coal mining is carried on below the Permian and Triassic, at a depth of more than 600 yards.

Another feature of the mining is the unique South Staffordshire mode of getting coal in the ten yard seam, called “Square Work.” This method has met with much condemnation from strangers, but after trial of other methods, it still dominates. A further and most strongly marked peculiarity of the South Staffordshire area is the tendency of some of the Black Country coals to spontaneous ignition. Much coal has thus in times past been sacrificed; but a better acquaintance with the causes of this phenomenon has led to measures which have reduced and which must still further reduce this sacrifice of wealth.

Mines’ Drainage.—In the Tipton and Old Hill districts many of the coal mines are water-logged. In 1873 a Parliamentary Commission however was appointed to drain this area, and was empowered to levy rates to defray the drainage expenses. The drainage area under the direction of this Mines’ Drainage Commission is 50 square miles. The principal pumping stations are the Moat, the Stoneheath Station, and the Bradley Station. The Bradley pumping engines (a quarter of a mile from Moxley on the Great Western Railway) are of the compound type having 52-inch and 90-inch steam cylinders. These engines, with a 10 feet stroke, and six strokes per minute, work two 27-inch plunger pumps, and raise from a depth of 126 yards more than 4,000,000 gallons of water per 24 hours. As a result of this gallant effort to recover these water-logged minerals, the number of pumping stations has been gradually reduced in the Tipton district from 77 in 1873 to 10 in 1885, and the quantity of water from 23,000,000 to 10,000,000 of gallons daily. To meet the inevitable expenses, a rate of 9d. per statute ton is levied on all coals, slack, and ironstone; 3d. per statute ton on all fireclay and limestone, and 1d. per statute ton for surface drainage on all minerals, raised in the Tipton district. In the Old Hill district a much lower mines’-drainage rate is collected.

LITERATURE.
Books, Papers and Maps bearing upon the Geology of the Birmingham District.

Fundamental Gneissic and Volcanic Rocks.