G.E. Lewis Barrel maker?

[James M. Warren 374]

This might be as promising a place as any to post this question:
My G.E. Lewis 8 Bore double rifle (circa 1879-80) barrels are stamped with the likely barrel makers initials "T.M." and barrels serial number 18845

I have been unable to narrow down who may have been the barrel maker. The museum in Leeds has been very kind to research, but nothing turned up.
Any ideas?
- Mike

[John 39]

G E Lewis was probably the a barrel maker these initials may have been the finisher's initials.

[James M. Warren 374]

Ledger page for the Lewis 8 Bore #5261 as researched by Royal Armories, Leeds
This was all they found, it is tough reading the old script!