Thanks Tom; very interesting observations and I now see the "Compression 850" mark. Every time you post we learn something. Thanks.
I must admit that I had never seen those marks on the barrel (1.330 kg) and your explanation is excellent. Wonder if they were purchased in Belgium then proofed in Saint-Etienne. The Stephenois were complaining about Belgian competition from at least 1878...I translated a letter by Didier-Drevet to the Saint-Etienne press in 1880 after a world's fair to this effect. Raimey should be along shortly to comment.
Traditional French checkering is the "basket weave style" like this on my "Wonder."
I'm wondering when the French went to the easier checkering as on this gun?
Again thanks. Gene Williams