"Coal and ironstone have been got in the township from an early period, but the numerous mines, furnaces, etc, which have stimulated the rapid growth of the town, were mostly commenced during the present century. The town has long participated with its neighbour, Wolverhampton, in the manufacture of locks, iron, tin, and japanned wares, and various articles in the iron and brass foundry lines, but a large portion of the inhabitants derive employment from the extensive mines of coal and ironstone, which furnish materials for the numerous smelting furnaces, foundries, forges, and slitting mills, which are carried on here to a vast extent. Many of the mines are wrought to a depth of more than 370 feet, and have various workable beds of coal, and below and above, several valuable strata of ironstone. Here are also prolific quarries of extremely hard and valuable stone, lying horizontally in twelve beds, some of which are said to produce the best grindstones and whetstones in the world, whilst others are wrought into cisterns, millstones, etc, and the coarser beds are used for building purposes. Here is likewise found a peculiar species of sand, of a deep orange colour, so very fine that it is scarcely palpable. It is much used in the casting of metals, and is sent for that purpose to various parts of the kingdom.
Immense quantities of rails, and other ironwork for the railways, have been manufactured here, and at Mr Spencer's extensive foundry and engine works, established in 1804, are made steam mills, forges, cranes, wheels, and all sorts of heavy machinery and castings used in the mining district. At the numerous ironworks around Bilston, the powers of the steam-engine, and other mechanical improvements, are extensively employed, and the hissing of the blast furnaces, the clanking of the forge hammers, the dusty appearance of the workmen, and the various operations upon unwieldy masses of red hot iron, combine to excite an idea of terror in those who are unaccustomed to such noisy and fiery scenes. Much of the ground about the suburbs of the town, is covered with the refuse of the mines, and the houses, in some places, are so much undermined, that large rents are often seen in the walls, and they occasionally fall so suddenly, as to leave the inmates barely time to escape.
Bradley moor is remarkable for an extraordinary phenomenon called a pseudo volcano, or wild fire, which has continued burning for the last 70 years, but it considerably abated 20 years ago, after reducing about six acres of land to a mere calx. It arises from a burning stratum of coal, about four feet thick, and eight to ten yards deep, to which the air has free access, in consequence of the main coal having been dug out from under it. The calx affords an excellent material for the repair of roads, and the workmen collecting it frequently find large beds of alum, of excellent quality. The surface is sometimes covered with sulphur, in such quantities to be easily gathered."
[From History, Gazetteer and Directory of Staffordshire, William White, Sheffield, 1851)