The Museum has recently borrowed a 6-inch breech loading gun and an associated hydro-pneumatic carriag dating to the late 19th century. It was known as a disappearing gun because after being fired from a position above the parapet, the force of the recoil would drive it downwards ready for re-loading. When ready for firing again, the gun barrel would be raised using the hydro-pneumatic system. The Museum’s disappearing gun is located in Eastney Fort East, only a short distance from the Museum. When it has been restored, it will be placed on display in a concrete emplacement that would have housed such a gun between the late 1890s and 1907.