Wheelbirks Furnace was a blast furnace used for smelting to produce iron. It is built of stone and was last fired between 1550 and 1590, making it the oldest known one of its kind in the region.
Smelting is the extraction of metal from its ore by a process involving heating and melting. Furnaces at this time were fuelled by charcoal and so were often built in wooded areas as charcoal didn’t travel well. Fuel (charcoal), iron ores, and limestone would have been continuously fed into the top of the furnace, while hot blasts of air air were blown into the lower section. Chemical reactions would then take place throughout the furnace and the molten iron produced would be tapped from the bottom.
This blast furnace ironmaking process was devised in what is now Belgium in the 15th century and the first one was built in England at Buxted in 1491. The medieval iron industry in Britain was concentrated in the Weald in Sussex and reached it’s peak around 1590. The first British furnaces outside the Weald appeared during the 1550s, and so Wheelbirks furnace is an important site in the study of the spread of that technology from south east England.
Charcoal-fuelled blast furnaces were replaced in the early 18th century by coke fired ones; these overcame the issue of local wood shortages and were cheaper to run.