Spittal build project brings new insight into brochs
AN architecture project held at Spittal has given a greater insight into early stone brochs in Caithness.
Caithness Archaeological Trust and the Archie Sinclair Fossil Centre, assisted by AOC Archaeology Group, undertook four weeks of experimental archaeology at Spittal Quarry, building an entrance to a life-size broch.
The intention of the STONEworks project was to build the entrance area of the broch to full height and then to test its stability in a number of ways.
AOC’s John Barber explained that the build did not quite go to plan, but the group did find out that the structures could have been hardier than first thought.
“Our prediction of the build was hopelessly optimistic,” he said. “However, we did build some 250 tonnes of stone into the wall, which reached almost two metres at its highest point.
“We expected to fully collapse the structure at the end of the project.”
A number of steel plates were built into the structure’s base and then pulled free while two web cameras and a laser level monitored movement. After three attempts the plates were removed, but instead of a building collapse the experiment left a hole some 1.5 metres wide and one metre high through the thickness of the wall.
John said that the broch showed remarkable resilience. “Given this ‘self-healing’ characteristic, it may be possible to punch a complete new entrance through the broch masonry without having to strip it down,” he said.
During excavations at Thrumster Broch in July, archeologists discovered evidence that the original entrance of the broch had been blocked, perhaps to help combat the effects of subsidence.
It was believed the broch had been partially dismantled to ground level and rebuilt to incorporate a new entrance in a more stable area.
But the findings at Spittal suggest it may have been possible to remove stones from the bottom and build a new doorway without the whole structure tumbling down.
The project will resume next spring. In the meantime experts will be looking at alterations in larger surviving brochs to see if they could credibly be identified as repairs, maintenance or modification of the original broch structures.
Community plays its part
AOC’s public archaeology officer Charlotte Douglas said that once again during the county’s summer of archaeology the local community played a vital part in making more breakthroughs at Spittal Quarry.
“Volunteers including local army cadets came to help with the building of the broch, and pupils from Keiss Primary School visited the site to learn about broch-building techniques as well as making their own Iron Age style pots,” she said.
“Artists and sculptors, including Tain artist Nicki MacRae, came to take inspiration from the broch-building process.
“The project also encompassed a series of talks, a guided walk and a very busy family activity day in Spittal Village Hall.”
Charlotte said that by learning about Iron Age building practices through imitation, they also gained an insight into the people who built Caithness’s brochs thousands of years ago.