Bob, thank you for all that information. As usual with any historical research, 14 new questions arise for every question satisfactorily answered! What your information does bring home is that the T series ranged from very basic models (like mine, with 0.5% engraved coverage!) through to examples with full engraving, gold inlay and detachable locks. One wonders what features actually defined the T series? I think I am going to have to invest the necessary 60/$100 and ask WR to send me a 'provenance certificate' for my gun, but first I shall have it put back into shooting condition.

Thanks again for your help. Appreciated.

Nigel.