Oops. It looked as though it would fit, just. But as we crept under a bridge in Hertford, the chimney's coolie hat started to scrape on the concrete underside of the bridge. The bridge, annoyingly, got lower the further under we went. I had tried to remove the chimney before going through, but it was stuck fast. So I hoped for the best. Mistake. The coolie hat was ruined, its rusted legs buckling and snapping.
I bought a new chimney hat at Beale Park, together with a flue brush. When I did eventually manage to work the chimney free, I found that the flue was caked with soot, and down to perhaps half of its original diameter.