First, thanks a lot for all your input! I hadn't expected to get so many replies.
As to the Sir George Filister jmm03 mentioned: Have you got any source for this?
I checked with the Shaw, William Arthur et. al.: The Knights of England. Sherratt and Hughes, London, 1906.
There is no Fillister, Filister, Phillister or Philister in the index.
But maybe it was only a good joke regarding all the threads Whitworth invented.
What I did find out in the meantime: It seems to be that the term fillister was used some time ago to denote a kind of grove in a metal or wooden object:
Collins states: a rabbet or groove, esp. one in a window sash bar for a pane of glass.
And Wiki yields two results:
- In "18 Warriors of Sui-Tang Period": ... The Tilu Spear was a long spear with a fillister near the spearpoint. When enemies were hit by the Tilu Spear, their blood would come out quickly through the fillister which might lead them to die...
- In "Hobe Fort": The sub-wall next to the barbette has a row of shell-shaped fillisters used for shell stockpiles.
Both the Wiki-entries relate to things Chinese. So maybe both texts were written by sinologists using a dictionary which was prepared centuries ago by a Portuguese or Italian monk.
But in Italian, Portuguese and Latin I could only find words with one "l" and pointing to our Philsters.
...so the mystery remains...
Have a nice weekend!