This gun, invented in 1911 by Commander Cleland Davis, USN, was developed to overcome the terrific recoil forces of artillery mounted in aircraft of the day. The gun consisted of a barrel open at both ends, a projectile, a propellant charge for it and a recoil weight behind the charge. The weight was designed to be expelled from the gun in the opposite direction of the projectile when the charge was fired. This would neutralize the backward thrust of the projectile and eliminate a vast majority of the shock on the aircraft framework. The Navy mounted it on seaplanes.