The "Featherweight" models were pre-1910
The post-1910 Knockabout with ejectors was $80 net
The No. 10 Quality was a non-ejector lightweight field gun at $100 net
The lettre annale is 'd' for 1925
The barrels are the time of proof weighed 1.397 Kg (maybe) = 2.97#. The gun is indeed a lightweight
I don't think I've seen a Francotte import marked 2 5/8"
The arrow points at what may be the crowned D of Delcour-Dupont tube maker, using Cockerill steel

[Linked Image from photos.smugmug.com]

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