Their Ben Turners control doors from a small entrance hall leading into their lounge and are believed were originally controlling the doors of what were once the main doors to the converted shop they now live in, parts of which were built in the 1600's, the doors themselves are mahogany.
The BT door springs were invented around 1872 and as you will see they will not be an easy repair especially as the whole spring mechanism and arms are missing from one and I believe the spring in the other is broken.
From looking at the patent, the spring is a clock type spring which I imagine to be quite wide.
More to follow as investigation progresses as to what exactly is the problem other than the obvious missing parts.