Our informal walking group often to be found on Isaac’s Tea Trail changed its name for our latest jaunt. No longer Isaac’s Tea Ladies, we became Isaac’s Floosies.
We were exploring the remains of the lead processing industry that dominated the Allendale area in the North Pennines during the 18th and 19th centuries. At the smelt mill beside the river East Allen the information panel showed the enormous scale of the processing and production.
The red lines mark the ducts that took fumes from the mill into massive flues that ran for more than two miles across the moors. When I first encountered these up above Allendale I’d assumed they were to channel toxic gases away from the town, but their primary purpose was to ensure that every last bit of lead was collected. As the fumes cooled lead and silver particles condensed onto the brick-lined walls of the flues and could then be scraped off. There are around 10 ounces of silver in a ton of lead ore and in the 19th century Allendale smelt mill was one of the largest producers of Northumbrian silver at more than 16,000 ounces a year.
The Victorian philanthropist Isaac Holden worked at a lead mine as a young boy, but later became a grocer in Allendale and raised money for good causes. The Tea Trail walking route named after him passes the entrance to the smelt mill, which would have been at peak production in his lifetime.
Most of the buildings have been demolished or had become overgrown, but a project by the Allen Valleys Landscape Partnership Scheme recruited volunteer archaeologists to help save the historic remains.
It isn’t possible to walk alongside the flues for the start of their route up onto the moors, but a bridleway crosses them around one mile from the smelt mill. The flue approaching from the east is a wide linear mound, then just west of the bridleway it splits into two tunnels which diverge to reach two chimneys more than a mile away on the horizon.
Returning to the road we walked past the hobbity-named Frolar Meadows and met the flues again as they tracked up across Flow Moss. Here a section of flue has been made accessible for close-up viewing, showing the stone arches of the flue and also one of the smaller tunnels used to get into the flue and scrape off the lead and silver deposits. According to Historic England, who designated the smelt mill and flues a Scheduled Monument, the system of flues is one of the best preserved in England.
As we walked up the clear path with a flue on our right it began to rain, not heavily but with a kind of suspended drizzle that soaked us and cloaked the wonderful views we could have been enjoying. In places the flue alongside us had collapsed, leaving the dogs intrigued about the giant rabbits that had made such huge tunnels.
As the rain continued we cut short our walk slightly by diverting to the nearest of the two chimneys. This is the smaller of the two at around 20 feet high and 23 feet in diameter. Its neighbour is taller and slimmer and together they are a distinctive landmark from many miles away in all directions. After posing for a bedraggled photo Isaac’s Floosies made their way off the moor to eat scones and drink tea.