maybe the most unusual 19 century sporting gun I have ever seen

google translator "SELL RARITY COLLECTOR CARABINER - Serial Number 35. Smooth brown barrel, in the area of the chamber okragonal, then cylindrical, caliber 10.5 mm. Lower part of the barrel with a test mark (St.Etienne). Smooth percussion lock with flap lock, opening lever on the right side of the frame. Removable shoulder rest and grip grips made of walnut wood. France 1856-1869, length with shoulder rest 82 cm. Probably EXPERIMENTAL MODEL"

https://aukro.cz/karabina-perkusni-zadovka-s-odnimatelnou-ramenni-operkou-rarita-6949503778

looks like a submachine gun

think such shooting walking sticks are forbiddenin many countrys but here is it

https://aukro.cz/unikat-skryta-pistole-v-holi-6960908924