Welsh Journals

Charcoal was burnt in the surrounding woodland, iron ore was brought from the Forest of Dean, Portskewett and Porthcasseg, and bloomery slag, which was used as a flux, was collected at Trellech, Monmouth, St. Briavels and Brockweir;4 in 1698 the furnace was producing 22 tons of cast iron a week.5 The majority of the pig iron was converted at the local forges for the use of the wireworks in the valley, but moulded casting sand found during the excavations indicates that some small scale casting of domestic objects may have taken place, and Torrington in 1781, refers to the casting of cannon.6 The furnace went out of blast in 1828 but was subsequently used by David Mushet, the Coleford metallurgist, for a series of experiments on the smelting of Indian wootz ore which were instrumental in establishing an advanced charcoal iron industry in India.7 The site was excavated between April 1979 and May 1980. The following is a description of the major features which can be seen today (Fig. 2). A-the Leat: the Angidy River was dammed f mile upstream of the site and a leat or water channel was carried from there to the water wheel at the furnace (E). For most of its length the leat was a stone lined trench cut into the natural, impervious clays, but in the final section its course is represented by a series of masonry pillars which would have carried a wooden launder, or trough, down slope to the wheel. B-the Ore Storage Area: this is represented by a sloping area of pitched and cobbled sandstone. Analysis of ore from here showed it to be hematite from Cumbria; the discovery of the rich Lancashire-Cumberland ore-field in the early part of the 18th century made it more economical to ship ore to Chepstow than exploit the local, poorer-quality, sources. C-the Charcoal House: a massive, rectangular building (49' x 23') for the storage of charcoal. The dominant species represented by the charcoal were oak, ash, beech and alder. D-the Bridge House: a rectangular building with an entrance lying under the modern road where the ore, charcoal and bloomery slag would have been mixed and weighed prior to charging the furnace. The north east end of the building leads directly onto the furnace top. E-the Wheel Pit: no trace of the wheel was found during the exca- vations but scour marks on the masonry walls of the pit suggest a wheel of 27' in diameter. F-the Blowing House: this building contained the blowing mechanism for the furnace blast. The shaft of the water wheel (E) extended across the building to operate a pair of bellows, which were replaced in c.1760 by a set of blowing cylinders operated from the wheel by a crank. Mushet8 states that these were the first cylinders to be used at a British charcoal furnace. G-the Furnace: although demolished to foundation level on three of its four sides it would seem that the furnace was a square, stone-