Page:Geology and Mineralogy considered with reference to Natural Theology, 1837, volume 1.djvu/401

 Rh frontier of the enormous Coal basin of South Wales, in the well-known Iron foundries, near Pontypool and Merthyr Tydfil, In the Transactions of the Natural History Society of Northumberland, Durham, and Newcastle, vol. i. p. 114, it is stated by Mr. Foster, that the quantity of iron annually manufactured in Wales is about 270,000 tons, of which about three-fourths are made into bars, and one-fourth sold as pigs and castings. The quantity of coal required for its manufacture will be about five tons and a half, for each ton of iron. The annual consumption of coals by the iron works will therefore be about 1,500,000 tons. The quantity used in the smelling of copper ore imported from Cornwall, in the manufacture of tin plate, forging of iron for various purposes, and for domestic uses, may be calculated at 350,000 tons, which makes altogether the annual consumption of coal in Wales 1,850,000 tons. The quantity of iron manufactured in Great Britain in the year 1827 was 690,000 tons. The production of this immense quantity was thus distributed,

lower region of this coal field are abundantly loaded with nodules of argillaceous iron ore, and below these is a bed of millstone grit capable of enduring the fire, and used in constructing the furnaces; still lower is the limestone necessary to produce the fusion of the ore. Pl. 65, Figs. 1, 2.

The great iron foundries of Derbyshire, Yorkshire, and the south of Scotland, afford other examples of the beneficial results of a similar juxtaposition, of rich argillaceous iron ore and coal.

"The occurrence of this most useful of metals," says Mr. Conybeare, “in immediate connexion with the fuel requisite for its reduction, and the limestone which facilitates