The craft of charcoal burning is a very ancient one, practised as early as 4,000 BC in Central Africa. The basic methods changed very little until the recent introduction of metal kilns. It has long been an important industry in the Weald, supplying the essential fuel for ironworking in the area. John Evelyn gives a detailed account of charcoal burning in his book Sylva, first published in 1664, describing the traditional methods which remained unchanged in this country until the Second World War. Of the 17th century market for charcoal, Evelyn writes: Of these coals the grosser sort are commonly reserved for the forges and ironworks: the middling and smoother put up in sacks and carried by colliers to London, and the adjacent towns; those which are char’d of the roots if pick’d out are accounted best for chymical fires and where a lasting and extraordinary blast is required. Today the demand for charcoal is limited to certain chemical processes, charcoal biscuits, artists’ pencils and fuel for barbecues, and the traditional craft of charcoal burning is dying out.