This is a scarce early production Mauser Model 1878 revolver with the hinged frame. The revolver was nicknamed Zig-Zag because of the parallel and inclined grooves machined into the outside of the cylinder which actually rotates the cylinder during firing. As noted this is the hinged frame model with the ring-type cylinder locking lever located ahead of the trigger guard, and a safety latch on the left side of the frame that prevents the cylinder from rotating when engaged. The top of the barrel rib is roll-engraved "WAFFENFABRIK MAUSER OBERNDORF A/NECKAR". The left side of the barrel lug has a double crown over a single "U" proofmark over serial number "2319". The back side of the ring lever, rear of the cylinder, lower locking lug on the frame and back side of each grip are correctly numbered "319". The revolver has the later style round-butt with the lanyard loop on the end of the butt. It is fitted with a two-piece set of hard rubber grips with a stylized floral and vine pattern around the edges with the center section being checkered. These pistols have a rust blue finish with a casehardened finish on the cylinder latch, trigger and hammer. These revolvers were later chambered in the 9mm Mauser cartridge, (forerunner to the 9mm Parabellum). Although very well manufactured and reliable, the Mauser Model 1878 was expensive to manufacture and had limited commercial sales. They remained in service with the German Army for 18-20 years until it was replaced by the 1896 Mauser pistol. Examples of this distinctive Mauser revolver are scarce.