Rare Principio Pig Above Farm Oven
13 April 2017 | 7 min read
When is a pig not in a sty? RPS’ Historic Environment team from Oxford, UK had an exciting surprise when appointed to advise on the heritage of a Devon farmhouse unusually featuring a built-in Iron Pig!
The Grade II Listed Steart Farm at Buck’s Cross, near Bideford, retains the traditional cob wall structure and the clay cloam oven inset into an end wall that is a characteristic feature of rural homes in the area, but the lintel of the cloam oven was less typical: it was an upside-down cast iron ingot stamped ‘PRINCIPIO * 1727’. This fitted with the finding of the Level 4 Recordi comprehensive historic analysis of the building that had dated the building to the late 17th/early 18th Centuryii, but was not the stone lintel that would be expected in this area.
The United Kingdom of Great Britainiii was successfully engaged in several international wars during the first quarter of the 18th Century including the lengthy Great Northern War (1700-21) and the War of the Spanish Succession (1701-14)iv . This was alongside a flurry of skirmishes between Scotland and England on British soil. By 1725 Britain had seen a neat run of victories and a couple of successful international treaties, and iron was in high demand for weapons manufacture.
Charcoal was a key component in the production of iron at this timev before the 19th Century, but the level of forest cover in Britain by the 18th Century was at its lowest ever point thus farvi . The nation could and had imported iron from Sweden but relations were not always stable during this time, especially with the countries opposing each other during the 20-year long Great Northern War. To resolve the issue, in 1719 a group of British investors established what was to be the first of several furnaces in the American colonies producing iron for UK use (from 1723). Their Principio ironworksvii in Perryville, Maryland, USA is estimated to have produced around half of the 50,000 to ns of pig iron ingots shipped from Maryland to the UK between 1718 and 1755. The ingots earned the name ‘Iron Pigs’ as each batch resembled a litter of suckling piglets and the 1727 purchase price at the furnace was £10.00 per ton. The Principio furnace was later destroyed by British troops in what is known as the War of 1812.
The answer as to how one precious ingot escaped the progress to London (a few consignments were shipped to Bristol and possibly Barnstable or Bideford) and then avoided manufacture into artillery – cannon barrels in particular – or other iron goods, is yet to be uncovered. Perhaps it was caught by the lull in British warfare at the end of the 1720s and was briefly a less valuable commodity, or found itself a guilty collateral damage in the industrial conflict between the Britain and US-based iron industries. Was it a valued object that proved a handy size and effective material for the oven lintel, or a concealed stowaway – hidden in plain but unremarkable sight? We don’t know, but it is an incredibly rare survivor of New World iron production – one of only very few stamped pigs discovered, and unique in its structural, and UK, location.vii.
RPS was appointed in 2013 to provide cultural heritage and ecology advice for the proposed construction of the Route 39 Academy school within the former Steart Farm camping and caravanning site on land once forming a part of the late 19th Century Mark Rolle estate. A part of the land previously used as a caravan site is to house the school building which secured planning consent from the Secretary of State in February 2016 following a Public Local Inquiry at which RPS Technical Director Mick Rawlings presented evidence with regard to cultural heritage. Planning consent was dependent upon the satisfactory completion of an Historic Building Level 4 survey of Steart Farm which sits within the site. The ground-breaking ceremony took place on February 23rd 2017.
The site sits within the North Devon Coast Area of Outstanding Natural Beauty (AONB), and adjoins/overlooks the Tintagel-Marsland-Clovelly Coast Special Area of Conservation (SAC). The site is enclosed by ancient woodland and incorporates with part of the Bucks Wood County Wildlife Site (CWS).
Environmental surveys across the site identified 11 bat species during transect surveys, and five more species roosting in small numbers during emergence surveys. Species protection and alternative roost creation is to be carried out in an existing outbuilding to maintain the value of the site for roosting lesser horseshoe, Natterer’s and pipistrelle bats.
A population of slow worms (protected under the Wildlife and Countryside Act) were successfully relocated within the site from the main construction site under a species protection strategy designed and implemented by RPS.
Completion of the slow worm relocation prior to the start of hibernation was fundamental to the project programme avoiding a six-month delay. Understanding how the slow worms were using habitats and targeting capture effort enabled successfully moving the whole population in autumn 2016. Prior to relocation new reptile habitat was created including hibernacula and log piles positioned in other nearby areas that are ideal habitats for the slow worm. A reptile barrier fence encloses the construction area and prevents reptiles entering the development site during construction.
The site is one of several that were being considered for the school’s location and is ideally situated to foster the school’s focus on outdoor learning and environmental values with minimal impact and providing a safe space for lessons. The main school itself will be two storey, using natural materials for its external face and set low in the surrounding landscape, on land previously used for caravans. New native tree and shrub planting will provide additional woodland habitat to deliver an acceptable biodiversity balance and strengthen the buffer between the school and the site boundary. This also reinforced the visual screening from natural viewpoints. Natural England advised that the school would be unlikely to have a detrimental effect and the Secretary of State ruled that its impact on visual amenity would be reduced to a minimum by its simple design, use of natural materials, careful setting and the additional planting
Steart Farm will be retained and incorporated within the school complex.
i An Historic Building Level 4 Recording survey requires a comprehensive historical and architectural analysis of a site or structure that researches and draws in a thorough range of evidence resources including visual record, mapping records, and building records. The results are presented with drawn, photographic and written accounts both contemporary and historic.
ii The main rectangle of the building is original, with the south-west extension dating to the mid-18th Century.
iii Established under an Act of Union in 1707, this comprised England and Scotland in the 18th Century. Wales was officially considered a part of England within the Act.
iv See Wikipedia for a quick potted history of Britain’s 18th Century wars.
v Coke started to be used in the process during the 19th Century – it has a higher crushing strength an helped facilitate the effective use of larger furnaces. Blast furnaces continued to use charcoal until the middle of the century.
vi By the end of the 19th Century the total woodland area of England was less than 5%. Sustained impacts from agriculture, animal grazing, industry, and landscaping fashions had all contributed to a substantial level of deforestation across Europe and the 18th Century saw heavy timber requirements for naval use and industrial use depleting the volume still further. Forestry Commission figures give the latest value at 10% (2016) – the turnaround largely due to conscious revegetation effort.
vii The Principio Iron Works offices are still standing. The building is listed on the National Register of Historic Places in the United States of America. Its reference number is 72000575.
viii : Other early Iron Pigs have been dug up in the USA close to furnace sites.