This is the very rare Lincoln Jeffries “Scout”. It’s a pop-out pistol that was manufactured between c. 1922 and 1926 during the dawn of the British airgun revolution. It was available either blued or nickel-plated. Many had no markings other than on the grip whereas a few were stamped “LINCOLN JEFFRIES JUNR 120 STEELHOUSE LANE BIRMINGHAM” on the front edge of the grip frame.