Case Study 14: Bonawe and Inverary Iron Furnaces

Bonawe and Inverary Iron Furnaces

Stefan Sagrott

The introduction of the blast furnace to Scotland appears to have been over a century later than its appearance in southern England in the 1600s. The early blast furnaces in Scotland operated side-by-side with bloomeries and are characterised by being operational for a fairly short amount of time, none longer than 16 years.

Two Argyll-based blast furnaces came to the fore of pig iron production in post-Culloden Scotland; Bonawe, Lorn (Canmore ID 23523) and Craleckan, Inverlecken (now Furnace) (Canmore ID 23401). Both furnaces were founded by established companies from Cumbria who brought with them a wealth of experience and skilled workers. Both took advantage of the regions plentiful & cheap timber as well as its easy access by sea to produce & ship pig iron at a price lower than in Cumbria.

The Bonawe Iron Furnace (Figure 114) was founded in 1753 by Richard Ford and Company beside the River Awe as it flows into Loch Etive. Timber contracts, running for 110 years, were signed with the local landowners, Duncan Campbell of Lochnell and the Earl of Breadalbane, and these provided unusually long security for the company; the remains of charcoal platforms and evidence for coppicing can be seen in the surrounding woodlands of Glen Nant.

The Bonawe furnace produced between 600 and 700 tons of pig iron a year using both local, seasonal workers and skilled ones brought up from Cumbria. The production was so great that it necessitated the construction of a new pier to cope with an increase in traffic. The furnace eventually shut down in 1876, a new lease having been signed in 1863, however the development of coke and steam furnaces mean that charcoal was an outdated technology, and Bonawe one of the last of its type in the UK.

Figure 114: Bonawe Ironworks Section and Plans © Historic Environment Scotland

The surviving buildings of the complex in the care of Historic Environment Scotland are two vast charcoal sheds, cathedral like in their proportions, with a capacity of 2663 cu meters, a long low building compartmentalised for storing iron ore and limestone and the furnace area with the furnace itself, the charging house, the fragmentary remains of the blowing house, the casting house and the lade. Beyond these are the extended pier, the manager's house and workforce housing along with a meal mill, store and school. Many of the architectural details at Bonawe such as the slate roofs & eaves of the buildings, and the red sandstone of the furnace are Cumbrian in origin.

Archaeological excavations in 1978-9 and 1982 concentrated on the area immediately around the furnace-stack and charging house, as part of an exercise to present the property to visitors. Whilst large-scale, they were by no means comprehensive, and significant archaeological stratigraphy remains, in both the blowing house and casting house. Although excavation also took place in and to the south of the charging house, most of the surfaces here were only superficially investigated. These excavations highlighted the fact, previously observed in the upstanding fabric, that the furnace had been modified during the course of its existence. In the blowing house, for example, the granite blocks supporting the replacement blowing cylinder were found, whilst the area between the blowing house and the casting house, originally open to the elements, was shown to have been subsequently built upon, to provide additional internal working space.

The potential for further archaeological research across the site remains high. For example, the discovery of four slate paths (probably barrow runs) between the iron-ore shed and the charging house demonstrates that further archaeological potential lies beneath the large expanses of grass. And although the upstanding roofed storage sheds appear to be archaeologically sterile, the two structures now surviving largely as foundations remain largely undisturbed.

The documentary evidence surviving for Bonawe allows a limited look into the social relations of those working there. Firstly, the workforce at the furnace itself, including their wives and families, comprised English-speaking incomers in a Gaelic environment and, from day one, formed a self-contained and isolated industrial community, complete with its own housing, school, church and inn. Secondly, although the core of the workforce were incomers (the furnace master and his men), much of the 'coaling' (charcoal production) was carried out by local people, taken on as seasonal workers to work in the woods the company leased

Figure 115: Cralekan site location (taken from PSAS 1984, 433-479) © copyright

Just after Bonawe was founded, another Cumbrian company, Duddon founded an ironworks at Inverlecken near Inverary on the north shore of Loch Fyne. The Craleckan Ironworks, similarly to Bonawe, undertook timber contracts with local landowners such as the Duke of Argyll providing security in its charcoal supply, additionally records indicate that coppicing was carried out in the nearby parish of Strachur (Figure 115).

It appears to have been similarly laid out to Bonawe but the complex is not as well surviving; the furnace is fairly complete and there are substantial remains of a charcoal shed of proportions able to hold around 7000 bags of charcoal. The documentary evidence for the furnace is scant but that available suggests it was on a similar production scale to Bonawe; both seem to have produced around 700 tons of pig iron in 1788 (Lewis 1984:439). Unlike Bonawe however, Craleckan also possessed a forge which allowed the pig iron to be worked into wrought iron.

Surviving at Craleckan is the sole-remaining furnace hearth in Scotland, and it is assumed that the very last blast remains in situ there.

Recent research in advance of an updated HES Statement of Significance for Bonawe has questioned some of the existing thought on the iron works, especially in relation to the interactions between the English and Gaelic speaking populations. The research has identified that in order to properly understand the site and its impact on Argyll at the time, a broader research framework needs to be defined; to both capture surviving oral history and also to look beyond the tight confines of the Property in Care boundary to ensure that the site is viewed as a full industrial landscape.

 

Bonawe Bibliography

  • Hay, G D and Stell, GP 1986 Monuments of Industry, Edinburgh
  • Historic Environment Scotland 2016 Historic Environment Scotland Asssessment of Significance: Bonawe Iron Furnace, Unpublished
  • Lewis, J H 1984 'The charcoal-fired blast furnaces of Scotland: a review', PSAS 114 pp. 433-479
  • Ritchie, J N G and Harman, M 1985 Exploring Scotland's heritage: Argyll and the Western Isles, Edinburgh