However...Bertram wasn't at Allensford or at least if he was, he was also at
Blackhall Mill which is down river from Shotley Bridge; not up apparently... and for which he was famous
I found this~ at
https://studylib.net/doc/8013653/the...lished-in-1773
Quote" The Swedish traveller Reinhold Angerstein, who visited Mather’s workshop in 1754, noted that he made ‘all kinds of steel hardware required for a watchmaker’s shop’, specialising in ‘a kind of grooved steel wire for pinions in small pocket watches’. The ‘raw material for the pinion wire’ at the time was ‘Mr Bertram’s Double Shear Steel’ from the North East, not crucible steel. Torsten Berg and Peter Berg (eds), R.R. Angerstein’s illustrated travel diary, 1753-1755: industry in England and Wales from a Swedish perspective(London, 2001), pp. 313-14. William Bertram operated at Blackhall Mill in the Derwent valley, the historic centre for the manufacture of shear steel."Unquote.
I have noted Angerstein before ... Wasn't he at Shotley Bridge for a meeting?