Not really, but I can combine a bit of French and schoolboy Latin.
That bit about the Dianas I don’t understand.
The rest appears mostly to be a standard description of how a tap-loading underlever works “when the lever is returned, the gun can be fired” kind of thing.
It says the basic model was the “Barton” and the deluxe version was the “Redcastle”. I think.
Feeling slightly smug to have discovered a - to us - previously unknown vintage rifle, and therefore expecting someone like Frank to pop up and tell us he has seven of them, with pics.