In 1681, the earliest blast furnace for smelting iron ore in Co. Galway was built by Sir Henry Waddington at Woodford. The furnace used local bog iron ore  mixed with rock ores from further south along Lough Derg, and timber, mostly oak, converted to charcoal.  

Blast furnaces in the 17th century were large square buildings with a side-length and height of approximately 5m.  The furnaces had two arches; the blowing arch where water powered bellows were placed and the casting arch where liquid iron and waste material were removed. 

The lintel of the casting arch bearing the date 1681 is the only ‘source’ we have which provides the start date of the Woodford iron industry and is now displayed outside the Heritage Centre on Bark Hill. 

Charcoal and iron ore were fed into the top of the furnace. Once it was full and lit, more ore and charcoal were added. The liquid iron was either poured into the shape of an object (cast iron) or into so-called ‘sows of iron’ which were destined for the finery to be re-melted into forgeable wrought iron.

A typical 17th century blast furnace would have had a daily production capacity of about a ton of cast iron or about 600kg of wrought iron. This required up to 10 ton of charcoal or the equivalent of half a hectare or 100m by 50m of woodland per day.