A metal of a bluish-white colour, of great hardness and elasticity; very malleable, and exceedingly tenacious and ductile. It is the most abundant, the most important, and the most valuable of all the metals. Although a simple undecompounded substance, it is not naturally found in this state, except in comparatively minute quantities, but is the product of art. Some specimens of native iron, nearly pure, have been found in Siberia and South America; also many iron stones, rich in the metal, supposed to be of volcanic or meteoric origin, have been found in numerous parts of the earth; but all the iron of commerce is obtained by chemical means. Iron is so universally diffused as to form a constituent part of almost all animal, vegetable, and mineral substances. Unlike metals of inferior utility, its ores are not distributed in thin veins, or scattered in minute particles, but are thickly stratified over many thousands of square miles, chiefly in the northern regions of the earth, where nature has been less profuse of her other benefits.
The use of this metal is of very great antiquity, though, on account of the difficulty of separating it from its ores, and of working it, probably not so remote as the employment of gold, silver, copper, and other comparatively soft, metals, which are in many places found in a pure metallic state. It is stated by some writers, that iron is mentioned by Moses as the material of which knives and swords were fabri cated; and that Herodotus mentions the presentation of a saucer, or vase of iron, very curiously inlaid, by Alyattes, king of Lydia, to the Delphic oracle. Later and more erudite writers have, however, maintained that the words of those ancient authors have been most incorrectly translated into our language; and that the working and use of iron was unknown at those periods. At what time the manufacture of iron was first attempted in Britain, cannot be precisely ascertained. Some suppose (for it is in reality only a probable conjecture) that the Phoenicians who wrought the tin mines of Cornwall, introduced into the country men who were skilled in metallic ores, and capable of estimating their value, by applying the minerals to such purposes as their own necessities or the wants of the inhabitants might require.
There is, however, much evidence to favour the belief that iron was worked in this country during the time it was in occupation by the Romans; and that during the establishment of the Danes in England, the arts of mining and manufacturing the ores of iron were much improved. It appears that the manufacture was at that period chiefly directed to the fabrication of malleable iron, in what were called fool-blasts, of a similar nature to those still used in remote uncivilized countries, of which Dr. Davy has furnished us with an example in a Singalese smelting house of the present day. The simplicity and cheapness of construction of this furnace is extremely interesting, as showing what may be effected by very limited means, and that the large capitals and immense laboratories employed by our present iron manufacturers, however necessary they may be to the production of a large quantity of the metal, are by no means essential to the production of a good quality; for it has been generally remarked, that the ruder the method employed in any country for the reduction of iron, the better the quality of the metal is. The observation holds good in Ceylon, and there is obvious reason why it should be correct.
Where the art is little advanced, the most tractable ores are selected, and charcoal is the fuel always used, circumstances which are alone sufficient to account for the iron obtained being excellent. Each furnace was, at its mouth, about 1 foot and 4 inches, by 8 inches in diameter; about 3 feet deep, and terminated in the form of a funnel, over a shallow pit inclining outwards. They were made in a bed of clay about 3 feet high, and 3 feet wide, against which a light wall, about 10 feet high, was raised to protect the bellows and operator, who was situated immediately behind. Each bellows consisted of a circular rim of wood, about 6 inches in diameter, and scarcely 2 inches high, fixed on a clay floor, and covered with moist cow-hide; in the centre of which was a hole to admit air, and to receive a cross stick, to which a cord was attached that was fastened above to an elastic stick. Each pair of bellows was worked by a boy, who rested his back against a rope for the purpose of support, and stepped alternately from the orifice of one bellows on to that of the other, at each step forcing a blast of air into the furnace through a tube of bamboo. The furnaces were charged with a mixture of iron ore, broken into small pieces, and charcoal.
The fires were kept up as strong as possible till the ore was reduced, and the fused metal collected in a cake in the ash-pit.
At the time when foot-blasts were used for separating the metal, the art of casting iron was either altogether unknown, or in a state that it could not be prosecuted with advantage. In the reign of Elizabeth, blast furnaces were of a sufficient size to produce, with ores and the charcoal of wood, from two to three tons of pig-iron per day, or from fifteen to twenty tons per week. It was only, however, in the most favourable situations for procuring water-power that such great products were obtained, and the greatest proportion of it was converted into bar-iron by means of the refinery fire; but in many of the small works the iron was "matured," that is, made malleable, before it was drawn from the furnace. Wood, however, becoming scarce, or being engrossed by the great manufacturers, induced several enterprising individuals to attempt the substitution of pit coal for making pig-iron. Mr Simon Sturtevant, 1612, had a patent granted to him, for thirty-one years, for that purpose. By the terms of his patent he was bound to publish the nature and process of his invention, which he did, in a quarto book, entitled Metallica; this book, Mr. Gray says, does not contain a particle of useful knowledge, but that it is an extremely curious specimen of the pedantry usual in James's reign.