““Indeed, the manufacture of iron had come into common use in Britain as early as the eighth century BC. It was discovered that heating iron-bearing ore to a high temperature with the use of charcoal, fanned by a draught of air, creates a solid lump of metal (a 'bloom'). When re-heated, the metal can be hammered into a shape. This is 'wrought iron'. If additional carbon is added to the ore, the melting temperature is reduced, which allows liquid iron ore to be poured into a mould. This is 'cast iron'. In the course of the fifteenth century, a furnace was developed which used blasts of heated and compressed air to drive up the temperature. This is a 'blast furnace'. The molten iron is run off into moulds consisting of a main channel connected to a number of shorter channels at right angles. As this resembles a sow suckling her pigs, the cast iron which results is known as 'pig iron'.””
