Jungson (Hubertus) Air Pistol.
See also:
https://forum.vintageairgunsgallery.com/hubertus/hubertus-air-pistols/#post-8773
See also HUBERTUS.
See also SNIDER
The Jungson was the predecessor of the Hubertus.
With thanks for these pics to Vaclav.
John Griffiths, author of The Encyclopedia of Spring Air Pistols, said: "I think it is quite possible that the Snider may be in fact the Jungson, rebranded and distributed by J.N. Oegland.
The early history of the Hubertus, and its transition from the Jungson to the small frame and then the large frame Hubertus is very confused and needs sorting out. Even the original patent by Fritz Jung is different from the commercially made pistols, and does not have the tip-up barrel, a ball pellet being dropped down into the breech though a hole on top of the cylinder."